Skip to main content

Full text of "Annual report of the National Bureau of Standards"

See other formats


• 



. 




NBS SPECIAL PUBLICATION 325 




TECHNICAL 
HIGHLIGHTS 




U.S. 

DEPARTMENT 

OF 

COMMERCE 

National 

Bureau 

of 

Standards 



UNITED STATES DEPARTMENT OF COMMERCE 

Maurice H. Stans, Secretary 
Myron Tribus, Assistant Secretary for Science and Technology 

NATIONAL BUREAU OF STANDARDS 

Lewis M. Branscomb, Director 

1969 
Technical Highlights 

of the 

National Bureau of Standards 



Institute for Basic Standards Institute for Materials Research 

Institute for Applied Technology Center for Radiation Research 

Center for Computer Sciences and Technology 

Annual Report, Fiscal Year 1969 




£ 



Special Publication 325 
Nat. Bur. Stand. (U.S.), Spec. Publ. 325, 243 pages (Mar. 1970) 

CODEN: XNBSA 

March 1970 



For sale by the Superintendent of Documents, U.S. Government Printing Office 
Washington, D.G. 20402 (Order by SD Catalog No. CI 3/1 0:325) - Price $1.25 



UNITED STATES DEPARTMENT OF COMMERCE 

Maurice H. Stans, Secretary 
Myron Tribus, Assistant Secretary for Science and Technology 

NATIONAL BUREAU OF STANDARDS 

Lewis M. Branscomb, Director 

1969 
Technical Highlights 

of the 

National Bureau of Standards 



Institute for Basic Standards Institute for Materials Researcli 

Institute for Applied Technology Center for Radiation Research 

Center for Computer Sciences and Technology 

Annual Report, Fiscal Year 1969 




Special Publication 325 
Nat. Bur. Stand. (U.S.), Spec. Publ. 325, 243 pages (Mar. 1970) 

CODEN: XNBSA 

March 1970 



For sale by the Superintendent of Documents, U.S. Government Printing Office 
Washington, D.G. 20402 (Order by SD Catalog No. CI 3/1 0:325) - Price $1.25 



Library of Congress Catalog Card Number: 6-23979 



FOREWORD 

This report on technical highlights of the National Bureau of 
Standards is valedictory in nature. The report covers fiscal year 1969, 
July 1, 1968 to June 30, 1969. Allen V. Astin, director of the Bureau 
for 17 years, retired on August 29, 1969. 

As Dr. Astin's successor, I am well aware that the progress evident 
in this and in the preceding 16 annual volumes reflects the determin- 
ing influence of a scientific administrator whose leadership strength- 
ened U.S. science and technology in an era of tremendous change. 
Building upon Dr. Astin's solid contribution, we hope in the years 
ahead to draw inspiration from his work and to rise to future chal- 
lenges in a similar spirit. 

Lewis M. Branscomb, Director 



in 



CONTENTS 

Page 

FOREWORD iii 

INTRODUCTION 1 

Staff and Organizational Changes 1 

New Deputy Director Named. Office of the Associate 
Director for Information Programs Established. Reor- 
ganization of the Center for Computer Sciences and 
Technology. Advanced-Research Teamwork With Uni- 
versities. Progress in Equal Employment Opportunities. 
Transfer of NBS-GSA Test Development Division. 
Programs Affecting National Policy and Consumer Problems.. 4 
Metric System Study. Automotive Safety. Broader Protec- 
tion from Flammable Fabrics. 
CENTER FOR COMPUTER SCIENCES AND TECH- 
NOLOGY , 7 

History oj the Program 7 

The NBS Computers. Research in Computer Components. 
Computer Applications. Establishment of the Center. Re- 
cent Activity. 

INSTITUTE FOR BASIC STANDARDS 21 

Physical Quantities 21 

International Base Units 21 

Length. Time and Frequency. Temperature. Electric 
Current. Fundamental Physical Constants. 

Mechanical Quantities 27 

Electrical Quantities — D. C. and Low Frequency 31 

Electrical Quantities — Radio Frequency 34 

High-Frequency Region. Microwave Region. 

Photometric and Radiometric Quantities 37 

Physical Properties 39 

Atomic and Molecular Properties 39 

Solid State Properties 47 

Thermodynamic and Transport Properties 49 

Mechanical Properties 54 

Applied Mathematics 55 

Technical Assistance to Others 57 

Advisory and Consulting Services 57 

Conferences and Symposia 62 

National Standard Reference Data System 64 

Current Activities 66 

Nuclear Data. Atomic and Molecular Data. Solid State 
Data. Thermodynamics and Transport Properties. Col- 
loid and Surface Properties. Chemical Kinetics. Data 
Systems Design. 
Information Services 71 



Page 

INSTITUTE FOR MATERIALS RESEARCH 73 

Preparation and Characterization of Materials 73 

Preparation 73 

Synthesis. 

Standard Reference Materials 95 

Data on the Properties of Materials 109 

Atomic and Molecular Data. Solid State Data. Thermo- 
dynamic and Transport Data. Chemical Kinetics. Surface 
Data. Mechanical Properties. Optical, Electrical, and 
Magnetic Properties. Reactivity and Corrosion. Engineer- 
ing Materials. 

Technical Assistance to Others 136 

Advisory and Consulting Services. Conferences and 
Symposia. 

INSTITUTE FOR APPLIED TECHNOLOGY 141 

Technological Measurements and Standards 141 

Building Technology 143 

Electronic Technology 150 

Systems Analysis 154 

Motor Vehicle Safety 156 

Engineering Materials 158 

Engineering Standards 160 

Technical Support Activities 162 

Technological Innovation and Diffusion 163 

Invention and Innovation 163 

CENTER FOR RADIATION RESEARCH 167 

Radiation Measurement and Standards 167 

Nuclear Physics Research 172 

Radiation Theory 174 

Structure of Materials 175 

Facilities Operations 176 

Technical Assistance to Others 178 

APPENDIXES 181 

Organization of the National Bureau of Standards 181 

Summary of NBS Staff as of June 30, 1969 188 

Financial Data for Fiscal Year 1969 188 

Research Associates and Guest Workers 188 

Advisory Committees 190 

Statutory Visiting Committee 190 

Technical Advisory Panels 191 

Awards and Honors 195 

Education, Training, and University Liaison 198 

Publications 200 

Publications in the Bureau's Series 200 

Publications in Outside Journals 210 

Patents 240 

vi 



INTRODUCTION 

Staff and Organizational Changes 

The National Bureau of Standards has continuing responsibility 
as the Nation's central measurement laboratory under terms of the 
Organic Act which created it in 1901 and through subsequent amend- 
ments to the Act. In addition, as a result of changing technology and 
through special legislative acts, new and expanding activities have 
been undertaken over the years. Changes in Bureau programs and 
activities have, not surprisingly, required redirection of administrative 
and management emphasis. 

Significant changes of the past fiscal year are discussed below. In 
each case, the change was designed to make the Bureau more responsive 
to needs of the commercial, scientific, and industrial groups which it 
serves. 

New Deputy Director Named 

Dr. Lawrence M. Kushner was named Deputy Director of NBS in 
May, 1969. He was previously the Director of the NBS Institute for 
Applied Technology. 

Office of the Associate Director for Information 
Programs Established 

The major organizational units at NBS that gather, analyze, and 
distribute technical information have been combined under an Asso- 
ciate Director for Information Programs. The new arrangement brings 
together related information activities that were previously managed 
independently. It permits improved coordination, common policy 
interpretation, and centralized and coordinated program planning, 
budgeting, and evaluation. 

The organizational components included in the new office are the 
Office of Standard Reference Data, the Clearinghouse for Federal 
Scientific and Technical Information, the Office of Technical Informa- 
tion and Publications, the Library Division, the Office of Public In- 
formation and the Office of International Relations. 



The information activities of the new office range from those of the 
Bureau's library, which primarily serves Bureau employees, to those 
of the Clearinghouse for Federal Scientific and Technical Informa- 
tion, which is responsible for disseminating technical information 
generated throughout the Federal Government. 

Dr. Edward L. Brady, formerly Chief of the Office of Standard 
Keference Data, has been appointed Associate Director for Informa- 
tion Programs. 

Dr. Brady came to NBS in 1963 to serve as Chief of the Office of 
Standard Keference Data. 

Reorganization of the Center for Computer 
Sciences and Technology 

The Center for Computer Sciences and Technology, established 
in 1966 in response to the Brooks Bill, has been made a separate orga- 
nizational entity reporting to the Director of the Bureau. The purpose 
of the Center is to develop standards and conduct research in the field 
of automatic data processing and to provide technical services to other 
agencies for improving the cost-effectiveness of Federal programs in 
the selection, acquisition, and use of automatic data-processing 
equipment. 

The Director of the Center, Dr. H. R. J. Grosch, received his B.S. 
and Ph.D. degrees from the University of Michigan. In 1945 he 
began his career in the data processing field with International Busi- 
ness Machines Corporation. In 1951 and 1952 he did logical design 
research at M.I.T. and later went on to manage project DEACON at 
General Electric's Center for Advanced Studies at Santa Barbara. 
From 1959 through 1965 he served as a consultant to major computer 
and information handling business concerns in the United States and 
Europe. Dr. Grosch has written articles on such diverse topics as celes- 
tial mechanics, lens design, numerical analysis, and the installation 
of computer operations. For four years he was a contributing editor 
of the journal, Datamation. 

Advanced-Research Teamwork With Universities 

Major moves toward increased cooperation with the Washington 
area's institutions of higher learning were made when the National 
Bureau of Standards entered into agreements with the University of 
Maryland and George Washington University to facilitate joint efforts 
in advanced scientific research. The agreements are a continuation of 
NBS efforts in the field of University-Government cooperation con- 
sistent with a White House memorandum in 1965 which encouraged 
sharing of laboratory facilities. In particular, these agreements are 



designed to encourage contributions to the Nation's research and 
development from young scientists early in their careers. 

The participating universities and NBS are providing for greater 
use of the Bureau's personnel and facilities in furthering graduate 
training and research, focusing university competency more strongly 
on work geared to national goals, and establishing machinery for 
close collaboration between each university and NBS in selected joint 
programs. Under the agreements, every effort is being made to attract 
distinguished scientists to limited-term appointments furthering the 
going projects, either at the Bureau or at the universities. University- 
related activities engaged in by NBS staff are considered part of the 
Bureau's normal activities, and activities of university staff and 
students on joint projects at NBS are regarded as part of normal 
university responsibilities. Supplementing the general agreement be- 
tween the University of Maryland and NBS, a specific memorandum 
of understanding has been adopted, providing for a Cooperative Pro- 
gram for Advanced Materials Research, teaming the Bureau's Insti- 
tute for Materials Research with the University of Maryland's Center 
of Materials Research. 

Progress in Equal Employment Opportunities 

During fiscal year 1969 several steps were taken to improve the 
NBS Equal Employment Opportunity Program. Among the steps 
were the strengthening of the EEO Committee, the establisliment of 
an Affirmative Action Plan for promoting equal employment oppor- 
tunity, and a vigorous information program, highlighted by meetings 
of the Director with the entire NBS staff explaining the Bureau's EEO 
program and enforcement procedures for non- discrimination rules. 
The Affirmative Action Plan defined short-term and long-term objec- 
tives for the program, pinpointed responsibility for the achievement 
of the objectives, and set target dates for their achievement. Objectives 
include improved training and job enrichment for minority employees, 
and monitoring efforts to assure adequate representation of qualified 
minority employees on promotion certificates and training class rolls. 

The Education Committee established a subcommittee to improve 
training opportunities for disadvantaged employees. Following the 
subcommittee's report, an adult basic education program has been 
planned to start in September, 1970, to prepare employees for tech- 
nician courses. A new position is planned for a full-time counselor on 
career development. 

Transfer of NBS— CSA Test Development Division 

For several years NBS has operated a testing laboratory for the 
General Services Administration to develop new test methods and 



run tests on specific commodities purchased by the Federal Supply 
Service. In keeping with the general NBS policy of developing and 
disseminating measurement expertise as widely as possible throughout 
other government agencies and private enterprise, the laboratory has 
been strengthened and transferred to the General Services Adminis- 
tration. The transfer of the laboratory is appropriate, since GSA has 
responsibility for qualified product lists and has the legislative author- 
ity to run a laboratory for testing products against standards. 

Programs Affecting National Policy and Consumer Problems 
Metric System Study 

Since the August 9, 1968 enactment of Public Law 90-472 authoriz- 
ing a Department of Commerce appraisal of "the advantages and dis- 
advantages of increased use of the metric system in the United States," 
the Bureau's exploration of the question in cooperation with other 
groups has indicated that the study will be concluded on time and that 
it will be possible to provide reasonable estimates for some of the 
costs of any major U.S. changeover to the metric system. 

The basis for estimated costs to firms has been laid by looking 
at potential costs as they would accrue if metric measurements were 
to be applied to new or redesigned products, stressing the concept of 
planning a transition — if there is to be a transition — at an optimal 
rate, without going back and changing all the drawings that are in 
the files. This method, it is felt, avoids the exaggerations and "astro- 
nomical" figures which would result from a doctrinaire approach 
based on an all-or-nothing plunge into metric measures throughout 
U.S. science and technology. 

Specialists conducting the NBS study have relied on the invaluable 
orientation guide devised by the American National Standards Insti- 
tute for companies making metric studies. In this approach costs are 
being estimated on the assumption that metric specifications will be 
used only for new, uniquely designed major components or end prod- 
ucts requiring new special tooling — only after new metric standard 
parts and materials are readily available at reasonable cost. This can 
be accomplished on an optimum schedule as present product designs 
become obsolete, on a timetable compatible with marketplace require- 
ments and normal tool obsolescence. In some areas — for example, the 
railroad and oilfield industries — changes in existing equipment do not 
appear to be warranted. 

Several questionnaires are being developed by NBS to aid in the 
study. Companies which have already looked closely into the advan- 
tages and disadvantages of increased metric use are being queried, as 
are other companies which have not attacked the problem in detail. A 
general questionnaire will be sent to both groups and their answers will 

4 



be compared. Large Federal agencies will be asked by the Bureau to 
gage the probable effects that "going metric" would have on their areas 
of responsibility. The Department of Defense, in particular, has a 
study team working intensively on the question of what the impact 
would be in the area of national security. 

A series of NBS conferences is being planned to gather further data 
and to provide an opportunity for representatives from the various 
sectors of the economy to present their points of view. 

An advisory panel has been organized to provide constructive assist- 
ance to the NBS Study Group. Members of the panel, which numbers 
almost 50, were selected from a broad cross-section of the economy. 

Great Britain's experience, and that of other nonmetric countries 
undertaking a changeover, is being analyzed in the NBS study to see 
what the United States can learn from their accomplishments and 
mistakes. 

The Bureau expects to present to the Secretary of Commerce a 
detailed report on both domestic and international implications of 
this issue — whether positive or negative — in order that the Secretary 
may recommend a course of action to the Congress. 

Automotive Safety 

An agreement between the Department of Commerce and the Depart- 
ment of Transportation was extended to continue the National Bureau 
of Standards Office of Vehicle Systems Research as an objective third- 
party resource to the National Highway Safety Bureau. 

One of O VSR's major activities during the year was working on a 
uniform quality-grading system for tires to allow for an informed 
choice by consumers. Objectives are to establish standard test methods 
for several important tire properties, define quality levels for each 
property, and develop a means of conveying the information to the 
consumer. 

Broader Protection from Flammable Fabrics 

Procedures for carrying out the Secretary's responsibilities under 
new and amended sections of the Flammable Fabrics Act were pub- 
lished in the Federal Register of October 1, 1968. They included rules 
for developing flammability standards by a four-step process. 

The NBS Fabric Flammability Section initiated research on the 
transfer of heat from burning fabrics and related materials, of hazards 
resulting from ignition of interior furnishings (beds and upholstered 
chairs), and development of a statistical sampling technique for 
investigation of deaths, injuries, and economic losses. 

After analyzing data from Consumers Union, the Department of 
Health, Education and Welfare, and other sources, NBS recommended 
to the Assistant Secretary of Commerce for Science and Technology 



that lie issue findings that there may be need for new or amended 
standards for both clothing and carpets and rugs. Accordingly, on 
October 23, 1968, notices were published in the Federal Register that 
new or amended flammability standards or other regulations, including 
labeling, may be needed for wearing apparel. On December 3, 1968, a 
similar notice was published, applying to carpets and rugs. 

The National Advisory Committee for the Flammable Fabrics Act 
was appointed, effective January 1, 1969. The committee's 17 mem- 
bers — representing manufacturers, distributors, and the consuming 
public — were selected by the Secretary of Commerce from among 
more than 50 nominations. The committee is expected to be particu- 
larly helpful in giving guidance on priorities for efforts both in test- 
method development and in research. 

The National Bureau of Standards organized a Symposium on the 
Measurement of Flammability. Several hundred attendees heard rep- 
resentatives of industry, government, universities, and the medical 
professions speak on the importance of heat, flame spread, toxic prod- 
ucts, and ignition characteristics of wearing apparel, mattresses, 
drapes, blankets, linens, furniture, and other items. 



CENTER FOR COMPUTER SCIENCES AND 
TECHNOLOGY 

In the quarter-century since the electronic computer made its debut 
in America, the National Bureau of Standards has been a leader in 
the development of what is now the fastest growing technology in 
the world. Greatly expanded since the forties, when early NBS re- 
search on computers was a partial function of the Ordnance Devel- 
opment Division and the National Applied Mathematics Laboratories, 
the Bureau's program in this field today is carried on by the Center 
for Computer Sciences and Technology under a Congressional man- 
date embodied in the 1965 Brooks Bill (Public Law 89-306). 

This law and supporting policy guidance from the Bureau of the 
Budget assigns to NBS the responsibility for: 

• providing guidance in the promulgation of hardware and software stand- 

ards, both for industry-wide voluntary standards and Federal standards 

• providing other Government agencies technical assistance and consulta- 

tion in both hardware and software areas in the efficient use of 
computers 

• promoting training in the various areas of computer applications 

• providing information services related to computer technology 

• providing computer services — both use of equipment and programming — 

to other Government agencies 

and 

• engaging in exploratory research. 

History of the Program 

NBS involvement in electronic computing machines began as a part 
of the Bureau's program of technical assistance to other agencies. In 
1946, two of them asked NBS to provide specifications and deal with 
manufacturers in the procurement of electronic computing machines. 
For the Bureau of the Census, NBS contracted with Eckert and 
Mauchley's Electronic Control Company for a UNIVAC; for the 
Office of Naval Eesearch, the Bureau contracted with the Eaytheon 
Corporation for a RAYDAC. Then the Bureau's own laboratories 
became fully occupied with a two-year program for the development 
of improved components for digital computers, carried out under 
sponsorship of the Office of the Chief of Ordnance, Department of 
the Army. 



The NBS Computers 

Work on the first UNIVAC followed an uncertain timetable be- 
cause of unforeseen technological and contractual difficulties ; delivery 
was made to the Census Bureau in 1951 after completion of extensive 
acceptance tests designed by Dr. Edward Cannon and Mrs. Ida 
Rhodes of the NBS Applied Mathematics Division. 

These were also the years of Project SCOOP (Scientific Computa- 
tion of Optimum Programs), a pioneering effort to apply scientific 
principles to large-scale problems of military management and ad- 
ministration. The Air Force's Office of Air Comptroller had requested 
that an NBS contract be amended to include a UNIVAC for Air 
Force program planning applications under the project, but delays 
in completion of both university and commercial machines led to a 
request for a "stopgap" installation. The Air Force asked the Bureau 
to launch a crash development program for a modest system desig- 
nated as the NBS Interim Computer, renamed SEAC (Standards 
Eastern Automatic Computer). In the summer of 1948, NBS explored 
possibilities of designing and constructing a machine with sufficient 
power for general use and yet simple enough to be constructed 
quickly. To supervise SEAC's construction, Samuel N. Alexander, 
then chief of the Electronics Division's electronic computer section, 
recruited from among von Neuman's group at Princeton a young 
engineer and inventor named Ralph J. Slutz. Working with some 30 
engineers and technicians, Slutz implemented the logical design of 
Dr. Samuel Lubkin, formerly of the University of Pennsylvania's 
Moore School of Electrical Engineering. When it became evident that 
the proposed SEAC computer would be the only equipment available 
to NBS and collaborating Government agencies for at least two 
years, the modest "interim" objectives were reconsidered. Dr. Slutz 
and his team made improvements and additions to Dr. Lubkin's 
original design and SEAC went into production in May 1950, just 
20 months after its inception. It was the first general-purpose, intern- 
ally sequenced electronic computer in operation in the United States, 
and provided the initial high-speed computing support to Project 
SCOOP until its UNIVAC was delivered in 1952. 

In additon to the UNIVAC's for Project SCOOP and the Census 
Bureau, a third UNIVAC for the Army Map Service was contracted 
for by the Bureau. Another computer, SWAC (Standards Western 
Automatic Computer), was being built at the Institute for Numerical 
Analysis, a section of the NBS Applied Mathematics Division, at 
Los Angeles. Operative early in 1952, SWAC differed from SEAC 
in using a parallel mode of operation. Its primary memory was com- 
posed of Williams tube units, enabling all digits of a number to be 
placed in memory or transferred simultaneously and arithmetic 
operations to be performed in parallel. SWAC's development was 

8 




SEAC, NBS's first computer, was completed in 1950. For the fourteen years of its 
useful life, SEAC was used by dozens of other government agencies ; portions 
of this computer are now preserved in the Smithsonian Institution. 



H 

I 




The NBS 1108/UNIVAC facility also serves as a service center for government 
and is available to all government agencies. Many users are served by computer 
terminals, some as far away as 2,000 miles. This modern facility is able to 
deliver results more than 1,000 times as fast as the pioneer SEAC. 



jointly sponsored by the Air Force's Office of Air Research, from 
interest in the performance of the machine itself, and the Office of 
Naval Kesearch, from interest in programming and mathematical 
research. SWAC was used in the solution of many aircraft problems 
by several Federal agencies; it was ultimately turned over to the 
University of California at Los Angeles, where it remained in use 
for 15 years. 

While working on SEAC and investigating the possible creation of 
other machines, Bureau specialists decided that SEAC's dynamic 
circuitry could lend itself to considerable electronic standardization. 
This is turn provided a basis for a repetitive physical configuration 
and the assembly of high-level pulse circuitry. 

The combined efforts of R. P. Witt and R. D. Elbourn produced a 
package design which, with some refinements, was used in two com- 
puting machines that were essentially modified copies of SEAC — 
FLAC at the Air Force Missile Test Center and MIDAC at the Willow 
Run Research Center, University of Michigan. 

NBS revised this package design to incorporate etched circuit 
techniques. Such packages were used in constructing DYSEAC, de- 
signed by A. Leiner, W. Notz, L. Smith, and A. Weinberger and com- 
pleted in 1954. This project was sponsored by the Research and Devel- 
opment Board for the evaluation of various organization and 
engineering innovations, among them the location of the equipment 
in a trailer for purposes of mobility. DYSEAC was used by the Signal 
Corps at White Sands, New Mexico. 

Combining digital and analog techniques, the Bureau solved several 
unique problems, such as the development (for the Weather Bureau 
and the Atomic Energy Commission) of a special-purpose computer 
for predicting the radioactive fallout pattern for a 250-mile radius 
from the detonation point of a nuclear device. 

Recognition of the need for a multi-processor stimulated the design 
of the Pilot Data Processor in the late fifties. Pilot combined a central 
processor, a satellite processor, and an input-output format controller. 
Used for experimental information processing in the early sixties, it 
was not considered feasible to move the one-of-a-kind vacuum-tube 
machine with its limited software to the new site when NBS shifted its 
headquarters from Washington to Gaithersburg, Maryland. 

Typical of new NBS projects in computer development to assist 
other agencies were the AMOS IV (Automatic Meteorological Obser- 
vation Station), designed to serve as the central element of an auto- 
matic system to process data for the Weather Bureau, and ACCESS 
(Automatic Computer-Controlled Electronic Scanning System) for 
handling information on the Nation's resources. 



10 



Research in Computer Components 

Originally sponsored at NBS by the Chief of Ordnance, Department 
of the Army, research on computer components gained impetus when 
basic components of the first UNIVAC for the Census Bureau had to 
be evaluated for performance and reliability. As specifications were 
being written for the UNIVAC, some research efforts were directed 
to the mechanical aspects of components such as tape drives and 
keyboards. 

Jacob Rabinow was heavily involved in this work, and as his group 
began to experiment with magnetic recorders using wire and tape, he 
invented the magnetic particle clutch in 1947. At the request of Army 
Ordnance, the Rabinow team initiated the design of a large-capacity 
magnetic memory which resulted in the notched-disc file in the early 
fifties. 

Efforts were concentrated on developing basic components, including 
storage devices, input and output equipment, and associated specialized 
electron tubes for such computing functions as gating, switching, 
delaying signals, interval timing, and pulse shaping. Two prototype 
high-speed memory units were developed, one using cathode ray tubes 
and the other diodes and capacitors as the storage units. 

One of the devices developed during this period was the magnetic 
wire cartridge, a simple input-output device that recorded on and 
read electrical pulses from magnetic wire. This was used in all of the 
automatic electronic computing systems designed and developed by 
NBS : SEAC, SWAC, DYSEAC, and the Pilot Data Processor, as 
well as in SEAC's two offspring, MID AC at the University of Michi- 
gan and FLAC at the Air Force Missile Test Center. 

Analog- digital techniques were used also in the design and imple- 
mentation by J. P. Nigro of NBS and his team of a man-machine 
systems simulator for the Wright Air Development Center and the 
Federal Aviation Agency. Resulting techniques were employed in the 
early sixties for designing MAGIC I and MAGIC II, cathode-ray 
display devices used with light pens as manipulative controls in con- 
junction with a computer in applications such as computer-aided 
design, electronic circuit organization, file information retrieval, lin- 
guistics, and others requiring computer graphics in the handling of 
two-dimensional information. 

Electro-mechanical problems associated with the transport and 
rapid start-stop features of the Rapid Selector engaged NBS attention 
as a result of Dr. Vannevar Bush's interest in this microfilm machine, 
which was able to search large amounts of data and retrieve particular 
sections by means of codes recorded on the film. At the same time, the 
Bureau continued research on the magnetic tape-handling device and 
the high-speed card punch. 



375-572— TO- 



11 



A corollary development was FOSDIC (Film Optical Scanning 
Device for Input to Computers) for the Census Bureau. FOSDIC, 
using optical, mechanical, and electronic techniques, scanned microfilm 
of hand-marked census forms and recorded the data on magnetic tape 
for input to a computer. So useful was FOSDIC for scanning forms 
and graphic material that advanced and more flexible versions were 
later devised not only for the Census Bureau but also for the Weather 
Bureau and the Office of Emergency Planning. 

After FOSDIC the next step — accomplished through another of 
Jacob Rabinow's inventions — was the development of OCR (Optical 
Character Reading) facilities, and an experimental model of a Best- 
Match Reading Machine emerged in the early fifties. This machine, 
demonstrated in 1954, is now on exhibition at the Smithsonian 
Institution. 

Computer Applications 

Mathematicians in this country and abroad were attracted to the use 
of the powerful tools represented by SEAC and SWAC. A large group 
of numerical analysis specialists was built up around each computer, 
devoting their efforts primarily to the development of linear pro- 
gramming techniques and the restructuring of equations for greater 
ease in handling by the machines. 

SEAC's first solution to a real problem was marked by the May 9, 
1950 successful run of the program for tracing skew rays through an 
optical lens system. This was programmed by Ethel Marden of the 
NBS Applied Mathematics Division. Mrs. Marden, with Otto Steiner 
and Ira C. Diehm, represented the entire programming staff for SEAC 
at that time, but additional personnel were recruited at a fairly rapid 
pace from the Bureau's mathematics staff, and a series of training 
courses in computer work was undertaken for NBS and other Gov- 
ernment employees. Outside personnel — including employees of other 
Government agencies, university staff members, and prominent foreign 
mathematicians — were frequently detailed to the Bureau for training. 

In addition to several optical problems, early applications were 
concerned with heat flow, analysis of crystal structures, and simula- 
tions related to wind tunnel designs, airfoil characteristics under vari- 
ous conditions, smog-producing factors, and statistical analyses. There 
was no lack of mathematical and scientific problems, both from within 
the Bureau and from other agencies, and they were of remarkable 
variety. 

Concentrated attention was given to two areas of mathematics : 

• Numerical analysis for investigation of series approximations and 
other numerical approximation techniques tailored for com- 
puter handling of mathematics (some of this work helped to 

12 



provide a basis for revised mathematics curricula at all three 
levels of the educational system) . 
• Algebra, matrix manipulation, and linear programing techniques 
(with applications for purposes of aircraft deployment and 
maintenance during the Korean war, in bid evaluation for the 
Army Quartermaster Corps, and in other fields) . 

In the early fifties, after SEAC made the first contributions to 
H-bomb design calculations, Dr. Allen V. Astin, NBS director, re- 
ceived a letter of commendation from the Atomic Energy Commission. 

Programing research and mathematical research for computers ad- 
vanced together at NBS. The Computation Laboratory, under Dr. 
Joseph Levin, developed a library of subroutines, including double 
precision and floating-point operations, and some of the pioneering- 
software such as "interpretive" programs. Joseph Wegstein devised a 
simple assembly language for SEAC in the early fifties. He chaired 
the international committee that developed the ALGOL language and 
was the first chairman of the committee that later developed the 
COBOL language. 

Early work on management information systems included studies 
for the Social Security Administration, the Treasury Department's 
savings bond division, and the Navy's Bureau of Supplies and Ac- 
counts. In the mid-fifties there were investigations of common process- 
ing problems such as sorting and file management. Ida Rhodes 
developed a combined sorting and file-merging program using push- 
down store techniques. For the Public Housing Administration a 
method of generating reports from raw data, based on automatic error- 
detection and logical-consistency checking techniques, was developed. 

Work on pattern recognition, pictorial data processing, chemical 
structure searching, and natural language processing also began in the 
mid-fifties. It gained impetus when, upon recommendation of the Bush 
Committee, a collaborative research program with the U.S. Patent 
Office was established in November 1954. Element-by-element chemical 
structure search (Ray and Kirsch) and HAYSTAQ, a searching sys- 
tem capable of multiple tracings of variable constituents of nodes of 
chemical structure representations (Marden), were demonstrated be- 
fore 1958. 

Interest in optical character recognition (OCR) began as an im- 
portant possibility for computer input. NBS supported work on a 
demonstration model of an electronic version of Rabinow's Diamond 
Ordnance Fuse Laboratory "First Reader" and surveyed OCR pos- 
sibilities for the Social Security Administration, the Rome Air De- 
velopment Center (RADC), and the Army Signal Corps, among 
others. Participation in OCR standardization efforts of the United 
States of America Standards Institute (then the American Standards 
Association) also began in the formative years of these efforts. 

13 



The RADC project involved general problems of pattern recogni- 
tion for which a programmable scanner (Kirsch, Calm, Ray, and 
Urban, 1957) was developed. It was applied to studies of local opera- 
tions on pictorial data (Thomas) , to continuing analyses of biological 
tissue data (Kirsch) and of micrographs of metallurgical specimens 
(Moore). 

Kirsch and Rankin in 1955 began taking a linguistic approach to 
pictorial data-processing, now continued by Rankin. The fifties were 
also notable for work on analysis of electrocardiograms in cooperation 
with the Veterans Administration (Marden) and traffic simulation 
projects (Stark). 

Among NBS contributions to natural language processing in con- 
nection with information selection, storage and retrieval systems were 
the development of a small-scale question-answering or fact-retrieval 
system (Stevens), the development of a KWIC-indexing system 
(Stevens), and experiments in automatic classification or indexing 
( Stevens and Urban) . 

DYSEAC, designed in 1951-54 by Leiner, Notz, Smith, and Wein- 
berger, was interconnected to SEAC to bring about a time-sharing, 
multiprogramming and multiprocessor capability. This mobile com- 
puter was used in conjunction with radar scanning and on-line display 
equipment to demonstrate air traffic control applications, and the in- 
terconnection of SEAC and DYSEAC was made in April 1954 in order 
to demonstrate multiprocessing. 

Ever since 1950, when the Bureau first was asked to advise the Post 
Office Department on automation, NBS has cooperated in the effort 
to provide increasingly sophisticated tools for carrying on this mam- 
moth operation. The Bureau's advice and assistance has covered the 
overall improvement of mail-handling, including mail-sorting codes 
and the design and selection of equipment ranging from keyboards 
and automatic mail sorters to automated post offices. 

After the Bureau acquired an IBM 704 in 1957, SEAC continued 
to be used solely as a research facility for equipment and programs 
until its retirement in April 1964. The 704, later followed by a 7090, 
a 7094, and a UNIVAC 1108, served not only NBS needs but also those 
of other agencies which either did not have computers or were not 
fully equipped in this area. 

With the move toward larger and more complex equipment, NBS 
computer work took new directions : 

• greater emphasis on sophisticated software essential to efficient 

functioning of larger computers 

• broader applications in data processing, complex file manipula- 

tion, pictorial data processing, library functions and document 
handling, large operations research Droblems. and others 

14 



• development of language and other user aids to increase pro- 

grammers' efficiency 

• standardization, 




This microfilm rapid reader-copier, designed and built by the Bureau for the 
National Library of Medicine, is an example of services provided to other 
government agencies by the NBS Center for Computer Sciences and Technology. 



15 



Establishment of the Center 

In response to the new responsibilities given it under the Brooks 
Bill, the National Bureau of Standards brought together several units 
in 1966 to form the nucleus of a new organization called the Center for 
Computer Sciences and Technology. 

The structure of the CCST reflects the nature of the additional 
responsibilities given to NBS and the broadened scope of its role in 
connection with computer operations in government. The underlying 
theme of that role calls for the CCST to improve the effectiveness 
and efficiency of the Government's use of computers. To that end 
emphasis has been focused primarily on standards and on providing 
technical advice and assistance to other agencies through computer 
systems design and development and through directed research in 
critical areas. Other functions include the operation of a computer 
service center for government and the provision of information on 
activities and personnel in the computer technology. 

The first director of the CCST was Mr. Norman J. Keam; he was 
followed by the present director, Dr. H. E. J. Grosch. 

Recent Activity 

During fiscal year 1969 the Center broadened its contributions to 
computer sciences and technology as employed both in the Federal 
Government and in the private sector. Among steps taken were : 

• Establishment of an official publication medium, the Federal 

Information Processing Standards Publications (FIPS PUB), 
for information relating to standards adopted and promulgated 
under the law. Nine FIPS PUBS were developed in fiscal 1969. 

• Implementation of the Federal Standard Code for Information 

Interchange and related media standards, through detailed 
instructions issued by Secretary of Commerce Maurice H. 
Stans to heads of Federal departments and agencies. The Code 
defines a set of 128 characters commonly used in information 
processing and communications. Among other things, instruc- 
tions are provided for new installations, replacements of com- 
puters, augmentation of existing configurations, interchange 
situations, and ADP /telecommunication interfaces. 

• Development of a new unrecorded reference tape standard, in 

cooperation with an NBS research associate sponsored by the 
International Business Machines Corporation. This work on 
amplitude reference magnetic computer tapes was undertaken 
at the request of both national and international magnetic-tape 

16 



standards bodies. The General Services Administration will use 
the resulting secondary tape standards for calibration of quali- 
fication test equipment. 

• Launching of a program, in cooperation with the industry, to 

develop a standard unrecorded magnetic reference surface for 
ready interchange of magnetic disc packs among equipments of 
different makes and models. 

• Establishment of a new Federal Information Processing Stand- 

ards Coordinating and Advisory Committee, with members 
representing the Bureau of the Budget, General Services Ad- 
ministration, Department of Defense, Atomic Energy Com- 
mission, and National Aeronautics and Space Administration. 
The new committee works through five inter- agency task groups 
on Transition to Federal ADP Standards. 
Federal adoption of a voluntary commercial standard for the 
COBOL programming language, approved and published — 
with the active participation of CCST staff — by the United 
States of America Standards Institute (now American Na- 
tional Standards Institute). This will facilitate the interchange 
of computer applications, programmed in COBOL, among 
Federal agencies. Work is continuing on the development of 
evaluation and validation routines, a necessary adjunct to Fed- 
eral adoption of the commercial COBOL standard. 

• Intensification of measurements automation research and develop- 

ment, emphasizing functional modularity and flexibile stored- 
program control — concepts which not only help to serve the 
needs of the Bureau's own laboratories but also appear with 
increasing frequency in commercially available instruments for 
making physical and electrical measurements and collecting, 
recording, and processing experimental data. 

• Technical assistance in cost-saving, efficiency-promoting opera- 

tions such as the application of digital computers and ADP 
technology to geophysical data-processing, fingerprint process- 
ing and identification systems, computer-controlled calibration 
of jet-fuel engine pumps, and development of a general micro- 
scope input for a computer (used at the National Institutes of 
Health). 

• Development of "anticipation techniques" and appraisal of fac- 

tors influencing optimum design of man-machine systems, as 
part of a point study in cooperation with the National Aero- 
nautics and Space Administration's Electronic Research Cen- 
ter. The new techniques are being applied in continuing 
experimental activity involving display and time-sharing 
equipment in NBS laboratories. 

17 



Development and study of hardware and software techniques for 
interconnecting various computer processors and peripheral 
equipment. The NBS-designed-and-constructed MAGIC II 
display terminal has been interfaced to the MOBIDIC B Time- 
Shared Computer Research Facility and several smaller devices 
have been attached to MAGIC II and MOBIDIC. 

Implementation of a general-purpose system for storing data and 
programs on disc files within the NBS CORD Time-Sharing 
System. The system employs novel techniques for improving 
access to files stored on disc and for improving the reliability 
of file storage. 

Utilization of the NBS CORD Time-Sharing System and the 
new disc file storage mechanism to help implement an informa- 
tion storage and retrieval system for data describing a special- 
ized collection of documents in the on-line systems and computer 
display areas. Besides being a useful tool to support the re- 
search program, this retrieval system is being used to study 
tradeoffs between manual and automatic search of a specialized 
data base with respect to the efficient use of manpower and 
equipment. 

Implementation, within the NBS CORD Time-Sharing System, 
of a conversational version of a language developed at Bell 
Telephone Laboratories for efficient list-processing. This sys- 
tem, designated CL6, incorporates compilation, execution, and 
debugging facilities in a flexible manner within a highly inter- 
active supervisory system. 

Development of a graphical assembler for generating display 
processor code on the larger time-sharing system, and imple- 
mentation of a graphical debugging system to minimize the 
time necessary for obtaining operational programs for display 
applications, taking into account the advantages of using the 
graphical display during the debugging process. 

Further development of a class of program generators that will 
enable an instructor to produce a Computer Assisted Instruc- 
tion (CAI) course as the result of an interactive process; and 
continuation of studies on the generation of "generators" in 
order to explore the possibility of using this approach to pro- 
duce computer programs of all types. 

Investigation of a programming language that (1) is a dialect 
of a standard programming language, hence uses an existing 
compiler; (2) permits content addressing, eliminating the need 
of a user to be concerned with the mechanics of search or 
indexing, and (3) permits dynamic creation of files for inter- 
mediate output or cross-reference indexes. 



18 



Application of two-dimensional linguistic techniques — used 
earlier by NBS for development of grammars from Chinese 
ideograms — to the analysis of other means of communication 
such as chemical-structure diagrams. Sponsored by the National 
Institutes of Health, the research is expected to extend the 
linguistics discipline and provide easier means of interfacing 
with a computer in the area of graphics. 

Experimentation with an information retrieval system for 
pharmacological data, designed for the National Institutes of 
Health, with special consideration given to the construction 
of numerous special-purpose files containing a variety of in- 
formation, including chemical structures. Such a system would 
help scientists to draw significant correlations of data for de- 
termining the effects of chemical substances on the body. 

Expanded design work for management and intelligence infor- 
mation systems applicable to tasks performed by the Agricul- 
tural Kesearch Service, the Public Health Service, and law 
enforcement agencies. 

Increased use of digital computers for automating experimental 
and research work in NBS materials and basic standards labora- 
tories. Computer-controlled data acquisition and control of 
experiments are now being widely applied to improve experi- 
mental accuracy and reproducibility, reduce errors and repeti- 
tive labor, more tightly control parameters, permit very high 
data rates and very lengthy experiment time, and increase 
experiment throughput. 

Collaboration with technical societies and professional orga- 
nizations to develop improved means for exchanging informa- 
tion recorded on magnetic tape, with emphasis on arrangements 
for sharing the task of descriptive cataloging and recording 
data elements in advance of the exchange of tapes. 

Drafting of a proposed plan for preparing a roster of sources 
of computer programs and documentation, and publication of 
a report embodying a "Recommendation for Formats for Com- 
puter Program Catalogs," based on an evaluation of existing 
formats and the information that should be available about a 
program in order to decide on its applicability to the solution 
of a specific problem. 

Initiation of a research project for extending the classification 
scheme for computer information. This is being carried on with 
the advice and support of the American Patent Law Associa- 
tion's subcommittee on computer information classification, in 
conjunction with the Association for Computing Machinery. 

Testing and evaluation of a simplified single-fingerprint identi- 
fication system designed to allow the computer code for a finger- 

19 



print to be easily written and sent to any central computer for 
a report on the probable identity of a suspect, amnesia victim, 
or corpse. 

Experimentation under the CCST's natural language processing 
program for purposes of improving information selection, stor- 
age, and retrieval systems; developing and using automatic 
classification and indexing techniques ; applying selective recall 
techniques to both associational files and natural language texts ; 
and developing on-line search strategies for text processing. 

Completion of selective literature reviews on Information Acqui- 
sition Sensing and Input, Information Processing Storage and 
Output, Overall Systems Design Consideration, and Privacy, 
Confidentiality and Security. 

Provision of data-processing services during fiscal 1969 to 60 
organizations including 10 executive departments, the Execu- 
tive Office of the President, and 15 agencies of the Government, 
the Congress, and State and local governments, quasi-govern- 
ment organizations, and universities. Assistance in evaluating 
and selecting automatic data-processing resources was given 
to the U.S. Civil Service Commission, U.S. Army TACFIEE 
headquarters, Commerce Department officials concerned with 
automated personnel systems, the Equal Employment Oppor- 
tunity Commission, and the Harry Diamond Laboratories. 

Development of operating software to handle remote access from 
keyboard terminals, expected to permit remote job and data 
entry from Model 33 or Model 35 Teletypes and to make possible 
future support of such applications as text editing, remote file 
inquiry, and conversational compilers. 

Installation of a "Graphical Display System" software package, 
developed at the University of California, allowing the user 
to generate a graphical display from his source program by 
using a standard set of simple specifications. The display can 
then be directed, by simple control card changes, to any of the 
available display devices. 



20 



INSTITUTE FOR BASIC STANDARDS 

The primary responsibility of the Institute for Basic Standards 
(IBS) is to provide the central basis for a complete and consistent 
national system of physical measurement, coordinating that system 
with those of other nations, and furnishing the essential services 
leading to accurate and uniform physical measurements throughout the 
United States. The IBS staff of 900 includes 528 scientists and engi- 
neers, 200 at the Ph.D. level, in facilities at Gaithersburg, Md., and 
Boulder, Colo. In addition to these primary locations, specialized 
activities are carried out at Fort Collins, Colorado ; Areata, Califor- 
nia; Maui, Hawaii; and an abandoned gold mine in the Colorado 
Rockies. The broad nature of the IBS responsibility requires work at 
many levels of technical sophistication ; however, the critical contribu- 
tions in measurement generally lie at the frontiers of science and 
engineering. 

PHYSICAL QUANTITIES 

The international system of measurement is based upon six quanti- 
ties: mass, length, time, temperature, electric current, and luminous 
intensity. All other physical quantities can be derived from these six. 
The United States and most of the other nations base their local 
systems upon these, but since it is impractical to make all measure- 
ments directly in terms of the base units, standards for the other 
physical quantities have been developed which are consistent with 
them. 

In a high technology society, the needs for better standards and 
means of measurement — more precise, stable, and easily disseminated — 
increase continually. Some of the current research in this area is 
described below. 

International Base Units 

Length 

Dynamic Distortion of Laser Rods Using Holography — Holo- 
graphic interferometry methods, and high speed photography have 
been combined to investigate the distortions of solid state laser rods 

21 



caused by optical pumping, lasing and subsequent cooling. In this 
technique, the optical wavef ront generated by passing continuous laser 
light through a passive rod is recorded in a hologram. If the wave- 
front then changes, interference fringes are produced by the hologram 
which interferes the recorded wavef ront with the new one. Distortions 
of the active rod create rapidly moving fringes which are photo- 
graphed using a high speed camera. The films thus obtained can be 
evaluated at a much slower speed and analysis of the distortion is 
readily made. Ruby rods have been tested using this method and a 
convex distortion has been observed at several pumping levels. The 
information obtained by this method will make possible the manu- 
facture of laser rods which are optically flat in the active state. 

Measurement of the Internal Diameter of Small Holes — The develop- 
ment of a new system for measuring internal diameters of small bore 
tubing utilizing capacitance techniques constitutes a significant 
advance in metrology, as well as contributing directly to the accuracy 
of the NBS gas thermometry program. The technique permits measure- 
ments at any position inside a tube up to 1 meter from its end, and can 
be used for tubes having diameters as small as 0.5 mm to an accuracy 
of approximately 14 /x in diameter. It has been used to measure the 
"dead space" that is part of the gas thermometer volume. 

Saturated A b sorption by Neon Inside a 6328 A Laser — The stability 
and reproducibilty of a 6328 A He-Ne laser locked to the saturated 
absorption peak of a pure neon discharge inside the cavity are being 
studied. In the He-Ne : Ne system however the pressure induced shift in 
the gain curve results in the situation where the absorption peak (due 
to the low pressure cell) does not occur at the maximum of the tuning 
curve. The frequency output of this laser is therefore expected to be 
sensitive to excitation conditions. It has been found that by utilizing 
the isotope Ne 22 in the absorption cell and a mixture of about 8 percent 
Ne 20 and 92 percent Ne 22 as the neon component of the gain cell the 
maximum of the gain curve can be shifted to the same frequency as 
that of the absorption peak. This is expected to increase greatly its 
usefulness as a wave-length standard. 

High- Ac curacy Laser — Since the invention of lasers, it has been 
assumed that they would eventually lead to an accurate standard of 
length. This has now been accomplished by stabilizing a 3.39 /mi 
helium-neon laser to the center of a methane infrared transition. The 
method used is known as "saturated absorption." The laser beam 
passes through a cell containing methane vapor at low pressure, and 
it partially saturates the methane transition so that the absorption 
coefficient is reduced. If the laser beam is tuned even one part in a 
billion away from the methane transition frequency, the saturation is 
substantially less and a greater amount of the laser light is absorbed. 
The resulting narrow peak in the transmitted laser light is used to 

22 



automatically keep the laser adjusted to the proper frequency. The 
shift with methane pressure has been shown to be very small. Two 
independent devices have been built, and their frequencies agreed to 
one part in a hundred billion. Such highly stabilized lasers may be 
used as the basis for a new definition of the meter which would be over 
300 times more accurate than the present definition. 

Time and Frequency 

World-Wide Standard Frequency and Time Signal System — NBS 
has traditionally provided strong support to the International Radio 
Consultative Committee (CCIR). This organization's Study Group 
VII (currently chaired by a senior NBS scientist) met in Boulder, 
Colo., in July of 1968 to discuss standard frequency and time signals. 
At the suggestion of the United States delegation, an international 
working party was set up to assure more active coordination on the 
important question of improving the worldwide coordinate time sys- 
tem, UTC. Reports initiated chiefly by the United States delegation 
led to international recognition of the conceptual distinction between 
time interval measurement (metric time) and coordinate time sys- 
tems and intervals. There was also recognition of the challenge posed 
by space and aircraft navigators who need a widespread synchornized 
timing system of high precision. 

Advances in Satellite Timing Techniques — New experimental statel- 
lite time dissemination experiments were conducted. The experiments 
utilized a synchronous satellite, positioned over the Galapagos Islands, 
designed to cover the Americas as well as some ocean regions. Primary 
design considerations were economy, simplicity, and versatility. A 
"listen only" technique was employed, eliminating the need for trans- 
mitting capabilities at user stations. In the first phase of the experi- 
ment, the basic timing format was tested; results indicate that the 
user can easily obtain an accuracy of 100 microseconds and that with 
more care 10 microseconds may be obtained. Voice announcements 
will be added at a later date. 

TV Time-Frequency Dissemination Studies — The use of television 
to disseminate time and frequency has been investigated. An initial 
study made use of a local TV station to synchronize the NBS WWV 
master clock at Fort Collins, Colo., with the NBS time scale main- 
tained at Boulder, Colo. TV synchronization pulses were monitored 
and the difference in their arrival time at the two locations was noted. 
With this information and accurate knowledge of the difference in 
propagation delay time between the two locations and the TV sta- 
tion, the time difference between the two clocks was obtained. Recent 
work between Boulder and Cheyenne, Wyoming, indicates that this 
method can be used to synchronize clocks to a few tenths of a micro- 
second. Besides its use in clock synchronization, television is a valuable 

23 



source of frequency information. Measurements made at Boulder on 
a 3.58 MHz color subcarrier originating in New York City have dem- 
onstrated that precision of a few parts in 10 11 may be obtained for 
15 -minute averaging times. Since the major networks use rubidium 
frequency standards in the generation of the color subcarriers, it ap- 
pears that there is very little degradation of the frequency information 
over the 4000-mile microwave path between Boulder and New York. 
An important aspect of these results is that the accuracies are orders 
of magnitude better than can be obtained with the WWV high-fre- 
quency broadcasts and yet they can be obtained essentially for the price 
of a TV set. 

Improved Stability and Accuracy of the NBS Frequency Standard — 
As a result of improvements in the stability and reliability of the 
NBS-III cesium beam frequency standard, a much improved cali- 
bration precision has been obtained for measurement periods from 
several hours to several weeks. A relative fractional precision was 
found to be 1.1 parts in 10 13 for o- (N=2, t=1 day, T = 7 days), based 
on two months of evaluation of NBS-III versus a commercial cesium 
beam frequency standard. An accuracy of 1.5 parts in 10 12 (3tr) is 
tentatively assigned to the improved NBS-III, based upon the most 
recent evaluation. 

Improved Timing Using LF and VLF — The usefulness of low fre- 
quency and very low frequency broadcasts has been improved by a 
careful analysis of phase propagation noise. Negative correlation of 
phase fluctuations was found between WWVL (20 kHz, Fort Collins, 
Colo.) andWWVB (60 kHz, Fort Collins) as monitored in California. 
Taking advantage of the negative correlation gave a factor-of -three 
improvement in timing. A similar improvement was obtained in a 
study of NSS (21.4 kHz, Maryland) and WWVL (20 kHz, Colo- 
rado). In this case a positive correlation of the phase fluctuations was 
found. In addition, the spectral densities of phase fluctuations of the 
NSS-WWVL paths and of the two driving oscillators were deter- 
mined. The corresponding optimum filter was applied to the data; 
when used simultaneously with the positive correlation information, a 
factor-of -ten improvement in timing was achieved. 

Completion of NBS-X4- Cesium Beam Tube — Construction of the 
NBS-X4 beam tube has been completed. Preliminary measurements 
indicate that the design goal of a figure of merit of 100 has been real- 
ized. (Commercial cesium beams have a figure of merit around 1-4. 
NBS-III currently operates in the range 5-10.) The beam tube was 
jointly constructed by NBS and the Hewlett-Packard Company, and 
will be combined with NBS -built electronics to form a much improved 
NBS frequency standard with a stability ten times greater than 
NBS-III. 

Time Scale Coordination with U.S. Naval Observatory — On about 



24 



1 October 1968, the universal coordinated time (UTC) scales main- 
tained at NBS and the U.S. Naval Observatory were in coincidence. 
At zero hours UTC on that date, the rate of UTC(NBS) was raised 4 
parts in 10 13 and the rate of UTC (USNO) was lowered 4 parts in 10 13 
in order that the divergence of these time scales would be at a much 
slower rate. Portable clock measurements have indicated time syn- 
chronization of the two scales to within ±5 microseconds, and agree- 
ments between USNO and NBS will guarantee that both are main- 
tained within this tolerance. The United States thus has, for the first 
time, a single coordinated time scale jointly maintained by USNO and 
NBS. 

Temperature 

Stability Improvement in Pyrometer Strip Lamps — The major limi- 
tation in the calibration of tungsten strip lamps used in optical 
pyrometry and radiometry is the instability of the lamps themselves. 
A theoretical model has been developed which explains the major fea- 
tures of these instabilities in terms of the changes that would be ex- 
pected to occur in the tungsten and lamp envelope due to temperature 
changes or prolonged heating at one temperature. This model has been 
used as a guide for the construction and heat treatment of 22 strip 
lamps. Of these, six exhibit a long-term drift of 0.01 °C in 100 hours, 
which is a factor of ten less than the best lamps previously available ; 
however, short-term temperature cycling of these lamps produces 
changes varying between 0.05 and 0.1 °C. Although it may not be 
possible to understand and reduce these cycling effects, the lamps will 
improve significantly the accuracy of high-precision optical 
pyrometers. 

Vapor Pressures of the Neons — The vapor pressures of Ne of natural 
isotopic composition, 20 Ne and 22 Ne were determined with respect to 
the NBS-1955 temperature scale from their triple points to their 
normal boiling points (about 14.5 to 27 K) . The results for natural neon 
were used by the Comite Consultatif de Thermometrie in its assign- 
ment of the neon normal boiling point as a defining mixed tempera- 
ture of the International Practical Temperature Scale of 1968. The 
measurements for the pure isotopes are about twice as precise as those 
for the natural mixture, where complete isotopic equilibrium possibly 
does not exist. Because of the possible variation in the isotopic com- 
position of natural neon (90.92% 20 Ne, 0.257 21 Ne, 8.82 22 Ne) the most 
abundant pure isotope, 20 Ne, is a more practical thermometrie standard. 

Superconductor Thermometrie Fixed-Points — A program whose 
aims are the extension to lower temperatures of the International Prac- 
tical Temperature Scale and the development of simple, accurate 
thermometry techniques has commenced with the examination of the 

25 



reproducibility on cycling of the superconduction transition breadths 
of lead, indium, tin, aluminum, gallium, zinc, and cadmium as meas- 
ured by magnetic induction. The transition breadths have been com- 
pared with the temperature-dependent resistance of doped germanium, 
and preliminary results indicate reproducibility in the range of a frac- 
tion of a fxK (both the doped germanium resistivity and the supercon- 
ducting transitions). 

A-G Thermometer Bridge — An improved resistance thermometer 
bridge has been developed. A frequency of 400 Hz was chosen for the 
bridge so that optimum performance could be obtained using commer- 
cially available operational amplifiers and decade voltage dividers. 
The bridge resolution is about 20 pK. when used to measure a standard 
25 O platinum thermometer at 0°C with a thermometer current of 
0.001 A. The bridge enables one to determine the ratio of an unknown 
resistor to a standard resistor. The bridge ratio is stable and has such 
high accuracy that the measurement accuracy is governed by the reso- 
lution of the bridge and the accuracy of the standard resistor. To 
measure the usual standard platinum resistance thermometer on the 
new bridge, additional connections are required — a pair of coaxial 
leads, which may be as long as 16 meters without affecting the accuracy. 
Values of resistance determined by this bridge agree with values deter- 
mined by a high quality DC bridge within the accuracy of the meas- 
urements. However, by contrast with DC bridges based on resistor 
networks, the ratios are stable without thermostating and do not drift. 
No lead reversals or auxiliary balances are required with this system, 
so that continuous recording of resistance versus time may readily be 
made. 

High Temperature Thermocouples — The development (supported 
by NASA) of reliable high temperature thermocouple probes, which 
are being sought for use in the design of nuclear reactors and thermi- 
onic devices, requires an understanding of the thermocouple behavior 
at very high temperatures in carefully controlled environments. Facili- 
ties were constructed for investigating performance of doped W-3 per- 
cent Ee and undoped W-25 percent Ee thermocouple wires at temper- 
atures of 2400 K and above when the thermocouple wire is subjected to 
high vacuum, argon and hydrogen environments. The changes in cali- 
bration of W-3 percent Ee versus W-25 percent Ee thermocouples 
were studied as a function of exposure time in these environments for 
time periods of 1 to 1000 hours. In addition, metallographic and chemi- 
cal analyses were performed to characterize material behavior. 

The results in vacuum confirm previous suppositions that evapora- 
tive loss of rhenium from the alloys at temperatures above 2200 K 
prevents their use as stable thermocouple elements. Stability with time 
in the carefully characterized argon and hydrogen environments was 
confirmed. 

26 



One of the more interesting by-products of this work was the dis- 
covery of extreme ductibility in the recrystallized doped alloy after 
heating in the vacuum environment. 

New Temper ahore Scale — NBS is calibrating thermometers on the 
International Practical Temperature Scale of 1968, which was adopted 
by the International Committee on Weights and Measures at its meet- 
ing in 1968. The Scale replaces the International Practical Tempera- 
ture Scale of 1948 (amended edition of 1960) . 

Electric Current 

Gyromagnetic Ratio of Protons in Water- Surveillance of the NBS 
Ampere — The precession frequency of protons in a magnetic field 
provides a convenient reference for the electrical standards ; however, 
fluctuations in the earth's magnetic field are a source of interference. 
A self oscillating rubidium magnetometer was set up at a distance 
from the proton sample, and phase-locked to a constant frequency 
source. The derived correction signal was used to maintain one com- 
ponent of earth's magnetic field essentially constant at both magnetom- 
eter and proton sample. Continuous detection of the precession fre- 
quency by the method of nuclear induction was found to result in 
improved convenience and reliability. By using the method of nuclear 
induction and compensation for changes in earth's magnetic field, the 
center of the proton resonance line can be located with an accuracy of 
about 1 part in 10 7 . 

Fundamental Physical Constants 

Measurement of Optical Frequencies — Modulation of a helium-neon 
laser with a 10 GHz microwave frequency has produced sidebands, 
v ± (o (where v is the laser frequency and <a is the microwave modula- 
tion frequency) yielding about 10 12 photons per second in each side- 
band for a 1 watt microwave excitation. With the addition of an 
optical spatial filter, a Fabry-Perot cavity and servo systems for lock- 
ing the laser frequency to the Fabry-Perot and the Fabry-Perot to the 
microwave frequency, the laser frequency has been locked to the micro- 
wave frequency with a precision, Sw/w, of about 1 part in 10 8 . It is 
hoped that the continuation of these experiments will yield the veloc- 
ity of light to the accuracy approaching 1 part in 10 8 (known at 
present to 1 part in 10 6 ) and that of light frequencies to 1 part in 
10 9 . The latter can be utilized in problems of standardization of length. 

Mechanical Quantities 

Microphone Calibration at Infrasonic Frequencies — As a result of 
research done at NBS over a period of several years, it is now possible 
to calibrate laboratory standard microphones at frequencies down to 



375-572—' 



27 



about 1 Hz with good accuracy, and a calibration service will be 
offered. This service should be valuable to those concerned with the 
measurement of low frequency noises, of which the sonic boom is a 
prime example. 

Precise Measurement in the Medium Vacuum Range — Accurate 
measurements in the medium vacuum range provide a firm basis for 
extension of measurement reliability into the higher vacuum ranges. 
These also satisfy a number of technical and scientific needs such as 
calibration of precision air data computers for high altitude flight and 
for atomic collision cross-section studies. Ultrastable vacuum environ- 
ments and a precision oil manometer allowed absolute measurements 
with an uncertainty of 1.2 X 10" 4 torr + 6 parts in 10 5 of the reading 
for the range 1 X 10" 4 to several torr. These procedures have now been 
extended with precision mercury columns as reference for inter- 
comparison with the oil manometer and for calibration of certain 
transfer gages. Calibration uncertainty in the higher range now ap- 
pears to be about 4 X 10~ 3 torr + 4 parts in 10 5 of the reading to 
25 torr. 

Hydraulic Research in the United States, 1968 — A new compilation, 
summarizing hydraulic research being conducted in university, gov- 
ernment, and in industrial laboratories in the United States and Can- 
ada was issued as NBS Special Publication 316. This issue summarizes 
1,690 research projects reported by 212 laboratories. Compilations of 
this nature are very useful in promoting contacts among researchers 
in similar areas and in preventing costly duplication of effort. 

Self -Calibration Procedure for the High Vacuum Range — A major 
difficulty in measurements at high vacuums is the lack of a convenient 
method for in situ self-calibration of working gages and of a suitable 
stable-transfer procedure. Fixed-point processes would be helpful. A 
method has been under study utilizing the dissociation of metallic ni- 
trides. Kesults for barium nitride show dissociation pressures ranging 
from 2X10- 5 torr at a temperature of 740 K to 0.7 torr at 1150 K. The 
slope of the In p versus 1/T plot corresponds to an enthalpy of reac- 
tion of 175 kJ/mol N 2 , which is consistent with dissociation into the 
subnitride, Ba 2 N, and nitrogen gas. The rate of approach to steady- 
state pressure is approximately logarithmic with steady values reached 
in time of about one hour. The steady-state values of pressures are 
dependent upon the direction of approach in pressure with the In p 
versus 1/T plot parallel but slightly displaced. Pressures are repro- 
ducible at present to within 10 percent. Present results suggest that 
such a technique may have application in vacuum calibration. Work 
toward improved precision and extension to lower pressures is in 
progress. 

Automated Vibration Calibration Facility — A facility capable of 
calibrating piezoelectric vibration pickups automatically has been 

28 



developed. It incorporates a small digital computer which controls 
the measurement in addition to acquiring the data. The facility makes 
it possible to collect considerably more data points than before, and 
to perform statistical comparison of the data with the previous cali- 
bration history of the pickup. The calibration at three times the 
number of frequencies can be done in one-third of the time needed 
before. 

Improved Transfer Standard Accelerometer — An improved trans- 
fer standard accelerometer has been developed for the calibration of 
working vibration pickups in or near field locations. These units will 
improve field calibrations by permitting the examination of the sev- 
eral motional components to which the pickups are subjected, thereby 
avoiding a common source of error. 

The transfer standard is unique in two respects relative to com- 
mercial units : ( 1 ) Instead of a metal housing, it has a ceramic housing 
which provides high stiffness, strength, electrical isolation, and sub- 
stantial weight reduction. (2) Eather than a single pickup for each 
acceleration axis, the new unit has three reference pickups mounted 
symmetrically about the vertical axis. They make possible a reliable 
monitoring of relative motion with respect to phase and amplitude 
of points over the shaker table surface. Other design features help to 
reduce loading effects and to produce a high resonant frequency, 
thereby increasing the usefulness of the device. The range of operation 
is 10 Hz to 12 kHz at acceleration levels to 100 g and with loads 
to 50 g. 

Strain Measuring Standard for High-Temperature Use — An ex- 
tensometer for use as a laboratory strain standard which employs a 
gas-cooled variable capacitor was designed and constructed for the 
U.S. Air Force Systems Command. Tests showed it to have a resolu- 
tion of 0.3 jum length change over a range of more than 2mm and to 
operate to at least 1400 °C in a normal atmosphere. A knowledge 
of structural strength at elevated temperatures is of urgent impor- 
tance in the development of gas turbines, rocket engines, missile and 
aircraft frames exposed to aerodynamic heating, and components of 
nuclear reactors. 

Misalinement Detector for Axial Loading Fatigue Machines — The 
alinement of the grips of an axial -load fatigue machine has a marked 
influence on the fatigue life of specimens tested in it. It is not pos- 
sible to measure these misalinements by ordinary means of linear 
measurement. To accomplish the purpose, a compliant element 
equipped with strain gages has been developed which is attached to the 
machine heads in parallel with the test specimen. As the specimen is 
cycled slowly through its loading excursion, the detector senses the 
minute deflections due to undesirable lateral forces. If these lateral 
deflections are found to be within allowable limits, the detector may 
be removed and the specimen tested in the normal manner. 

29 



Internal Wave Generation — Under sponsorship of the Office of 
Naval Research, a study was made of the internal waves created by 
the steady horizontal motion of a sphere through a liquid having 
a uniform rate of density increase with depth. A new theory was 
developed for this three-dimensional problem which closely approxi- 
mates the experimental results. Most of the previous work in this 
area has been restricted to analysis in only two dimensions. Wooden 
spheres, having radii from 2.4 to 4 cm, were towed to speeds up to 
5 cm per second through fluids having total density differences of 
0.9 to 6.7 percent over 50 cm of depth. This permitted a wide variation 
in flow parameters without excessive turbulent wake formation and 
mixing. The vertical fluid movements, which were only a few milli- 
meters, were measured by a wire probe. 

In addition to contributing to the understanding of internal wave 
generation in the oceans, the new theory will be useful to meteorolo- 
gists studying the generation and effects of lee waves behind moun- 
tains. These are of particular concern to the aviation community, 
contributing to the dangerous phenomenon known as clear air turbu- 
lence (CAT). 

Small-Scale Structure of Turbulence — In collaboration with the 
Naval Ship Research and Development Center, and with the partial 
support of the Atomic Energy Commission, an experimental investi- 
gation of the small-scale structure of a turbulent field was carried out 
by extending the methods of digital analysis to the measurement of 
turbulent velocity derivatives. The statistical behavior of these deriva- 
tives was studied in the nearly isotropic decaying turbulence field 
generated by a 1-inch square mesh grid in the NBS 4% -foot wind 
tunnel. Higher-order correlations for velocity gradients up to the 
eighth order, at two stages of decay, and for a limited change in 
Reynolds numbers have been determined. Markedly different from the 
turbulent velocities, the higher-even-order correlations of velocity 
gradients clearly evidence the departure from a two-dimensional 
Gaussian probability distribution, and more clearly exhibit similarity 
with a characteristic length or time scale. The results require that 
current views as to the intermittent character of the small-scale 
structure, at least for the Reynolds number range of the present inves- 
tigation, have to be carefully evaluated. It is expected that investiga- 
tions of this type, under laboratory-controlled conditions, can play 
an important role in the understanding of the turbulence structure and 
provide insight into closely related problems associated, for example, 
with atmospheric turbulence. 

Heated- Air Adiabatic Saturation Psychrometer — A humidity-meas- 
uring instrument, based on the heated-air adiabatic saturation prin- 
ciple, and suitable for use in both laboratory and field, has been 
designed and constructed. With it, the moisture content of atmospheric 

30 



air can be measured over a mixing ratio range of to 50 g of water 
vapor per kilogram of dry air; in terms of dew point, this range is 
— 40 to +40 °C. When compared with the NBS two-pressure humidity 
generator over a mixing ratio range of about 2 to 19 g/kg, the mean 
difference was 0.046 g/kg and the maximum difference was 0.12 g/kg ; 
the corresponding differences in dew point were 0.08 °C and 0.30 °C, 
respectively. The instrument is portable and self-contained, requires 
a 110- volt, 60-hertz, 2.5 -ampere power source, and a barometer. It 
samples test gas at a gas-flow rate of 4 liters per minute. 

Electrical Quantities — D.C. and Low Frequency 

Current Transformer Calibration — A compact and versatile meas- 
urement system for calibrating current transformers at power fre- 
quencies has been developed. The system based on the current 
comparator principle, permits calibration of all ratios normally 
encountered (to a maximum of about 12000/5) , and features the capa- 
bility of testing transformers at operating currents up to four-times- 
rated. It provides those laboratories concerned with power and energy 
measurements with a method for calibrating their current transformers 
to improved accuracies with minimum recourse to the NBS facility. 
For transformer ratios up to 1200/5, the measurement accuracy is 
within 5 ppm for both the ratio factor and phase angle. Calibrations at 
ratios greater than 1200/5 are limited by the NBS calibration accuracy 
of standard transformers, but can be typically made to 50 ppm or 
better. 

High Voltage Capacitance Bridge — A high-voltage capacitance 
bridge based on the current comparator principle has been constructed. 
In this bridge a three- winding current transformer or current com- 
parator forms the ratio arms, offering unequaled accuracy, stability, 
and sensitivity. In contrast with conventional high-voltage bridges, 
the dissipated power is very small and does not affect the accuracy 
when capacitors of high volt-ampere rating are measured. With this 
bridge, it is possible to calibrate a broad range of capacitors: from 
100 pF to several thousand fiF. The voltage range of the bridge is 
from 100 to 200,000 V, the upper limit depending only on the avail- 
ability of a high-voltage capacitor. The direct reading accuracy with 
which two capacitors can be compared is within 2 ppm for small 
ratios and within 10 ppm for the largest ratios (2 X 10 6 : 1) . The instru- 
ment is designed to calibrate those items which cannot be accommo- 
dated on existing NBS low- voltage bridges: high- voltage capacitors 
and power factor standards used by the manufacturers of high- voltage 
equipment. 

International Comparison of Capacitance Standards — Another 
comparison circuit of three 10 pF fused silica capacitors has been 
completed, this time at laboratories in the Union of South Africa, 

31 



France, and at the International Bureau of Weights and Measures. 
Measurements made at NBS show that the capacitors continue to 
remain stable to about one part in 10 7 . 

Improved Techniques for Audio Frequency Admittance Measure- 
ments — A number of bridges suitable for comparing four-terminal- 
pair admittance standards, including a so-called quad bridge for 
comparing resistance with capacitive reactance has been developed. 
Many simultaneous null conditions must be realized with these bridges, 
but suitable techniques have been developed for achieving the re- 
quired conditions quickly. A ree valuation of the defining conditions 
for four-pair standards, and the development of techniques for as- 
sessing the errors due to insufficient suppression of ground currents 
with coaxial chokes, have made it possible to reduce the measure- 
ment errors below one part in 10 9 . 

New Base of Reference for the V olt \ Adopted — On January 1, 1969, 
the United States, along with eight other countries, on recommenda- 
tions of the International Committee on Weights and Measures, 
adopted a new base of reference for the volt. In the United States 
the new base differs from the old base, used prior to January 1, 1969, 
by 8.4 parts per million. This means that the electromotive force 
(emf) obtained for a standard cell is now higher than that obtained 
on the old base of reference by a factor of 1.0000084. The new value 
represents a better measurement of voltage in terms of the theoretical 
unit of emf derived from the basic mechanical units of length (meter) , 
mass (kilogram), and time (second). This change came about as a 
result of absolute measurements made on the ohm and ampere since 
January 1, 1948, when the International Committee on Weights and 
Measures recommended a conversion from the "international" elec- 
trical units to the "absolute" system. 

Comparisons of the Unit of Electrovnotwe Force at BIPM, NRG, 
and NPL — International comparisons of the unit of electromotive 
force are made approximately every three years by the Bureau Inter- 
national des Poids et Mesures (BIPM). Each country participating in 
the experiment sends a group of saturated standard cells to BIPM, 
and on the basis of measurements made at each national laboratory 
and BIPM, differences between the units of emf maintained by the 
various countries are determined. This comparison usually requires 
6 to 8 months to complete. In cooperation with BIPM, the National 
Research Council of Canada, and the National Physical Laboratory 
of Great Britain, an experiment was conducted in which a group of 
saturated standard cells in a temperature-controlled enclosure was 
shipped to the various laboratories. A complete experiment between 
NBS and the participating laboratory required only 3 to 6 weeks; 
the two intercomparisons between NBS and BIPM showed excellent 
agreement between the "rapid" and conventional methods. The means 

32 



of the two rapid intercomparisons differed by 0.2 ppm from the conven- 
tional method. Additionally, this excellent agreement serves to verify 
the adjustments made to the NBS unit on January 1, 1969. 

Inductive Voltage Divider — Aerospace industries require high ac- 
curacy in the voltage ratio standards used for calibration of guidance 
and control equipment. Commercially available inductive voltage 
dividers suffer from several limitations, the most serious being the 
nonindependence of the corrections to one decade with respect to the 
setting of the others. Several single- decade inductive voltage dividers 
have been designed, constructed, and cascaded. The results show that 
it is entirely feasible to construct multidecade dividers having overall 
errors two orders of magnitude smaller than the presently available 
ones. The single- decade units utilize the multistage voltage trans- 
former principle and an impedance compensating network, and show 
output-to-input voltage ratio errors of approximately 1 part in 10 9 . 

Precise EMF^s from the Microwave Josephson Effect — Instrumen- 
tation has been developed for the precise comparison of standard cell 
voltages with the emf 's produced by microwave Josephson junctions 
operating at a temperature of two kelvins. These junctions act as very 
precise frequency-to-voltage converters making possible the transla- 
tion of standards of radio frequency into independent, nonelectro- 
chemical sources of d-c electromotive force. 

High-Intensity Electric Field Measurements — An electro-optical 
technique which utilizes laser light for analysis of high-intensity 




The electromagnetic field within a Kerr cell is rendered visible through use of 
polarized laser light. A typical fringe pattern is shown in the insert. 

33 



electrostatic fields has been developed and used for the measurement 
of distorted fields obtained when high direct voltages (to 90 kV) are 
applied to nitrobenzene-filled Kerr cells. The field can be mapped 
from fringes produced by the Kerr effect. This technique, which was 
developed to permit calibrations of Kerr pulse-measuring systems, 
offers several advantages over conventional field-mapping techniques, 
including the following: (1) the two-dimensional visual images, 
similar to those achieved in photoelastic mechanical stress analysis, 
permit direct observation of the field distribution, thereby enabling 
immediate detection of regions of high electrical stress; (2) space- 
resolved measurements of field strength and potential are obtained 
from a single photograph; (3) measurement resolution increases with 
the magnitude of the field ; and (4) a laser source allows simplicity in 
the optical system. It is anticipated that this technique will also be 
useful in electrical stress and breakdown studies, in high-intensity 
field-mapping experiments, and in investigating the behavior of many 
dielectric liquids. 

High-Voltage Pulse Measurements System — A system which gen- 
erates and measures high-voltage pulses ( rise-time ^ 1 ju,s, duration ?« 
4 /xs) has been designed and constructed. This system, which received 
partial support from the Atomic Energy Commission through the 
Sandia Corporation of Albuquerque, New Mexico, is equipped for 
time-resolved, simultaneous, voltage divider and Kerr electro-optical 
measurements of pulses peaking between 5 and 300 kV. 

Electrical Quantities — Radio Frequency 
High-Frequency Region 

Design Data for Impedance Standards — NBS uses quarter-wave- 
length short-circuited sections of waveguide as reference standards 
for calibrating microwave impedance standards. These waveguides 
can be accurately evaluated and have the additional advantage that 
losses at the place of connection are negligible. In order to make these 
reference standards more available to other laboratories, design data 
have now been published. The data consist of a series of computer- 
calculated curves of return loss versus frequency for each of the 
standard sizes of rectangular waveguide and coaxial line presently in 
use. The curves are normalized to a conductivity of 10 7 mhos/meter 
and can be read to ±2 percent, which gives sufficient accuracy for many 
purposes. In case greater accuracy is required, formulas are given 
for the calculation of return loss. Using these data, any interested lab- 
oratory can design and construct accurate impedance standards and 
improve the accuracy of their impedance measurements. 

Primary Standard Coaxial Noise Generators — Two precision, co- 
axial, thermal noise generators were designed and constructed for 
use as primary standards of noise power in the high-frequency range. 

34 




Precision coaxial thermal noise generators for use as primary noise power 
standards at frequencies from 3 to 100 MHz. 



At present both operate at either 30 MHz or 60 MHz, but they can be 
modified to operate at any frequency between 3 and 100 MHz. One 
generator, using a bath of liquid nitrogen, has a noise temperature of 
approximately 76 K with an uncertainty of 0.10 K. The other, using a 
bath of heated fluorochemical liquid, has a noise temperature that is 
adjustable between 300 K and 500 K with an uncertainty of 0.15 K. 
These standards are used to measure high frequency random noise 
sources having temperatures between 75 K and 30,000 K. 

Baseband Pulse Transmission — Frequency and time domain analyses 
of normally conducting coaxial cables at low temperatures have been 
performed. The anomalous and classical skin effects were considered by 
employing the Reuter and Sondheimer anomalous skin effect theory. 
Frequency and time domain response versus temperature (4 to 300 
K) has been predicted for six miniature commercial coaxial cables and 
one Nb-Pb superconductive cable maintained in the normal state. Grood 
agreement was obtained with available time domain data, both directly 
and by application of Fourier transform techniques. The methods 
developed in this work provide a means for computing transmission 
characteristics in the presence of temperature gradients along a coaxial 
cable such as would be encountered between a cryogenic environment 

35 



and ambient space. From this information, pulse distortion in the cable 
can be predicted. Similarly, this technique can be used as a means for 
pulse shaping to predetermined requirements. 

Improved Pulse Power Meters — NBS has been instrumental in the 
recent commercial development and manufacture of three improved 
RF pulse power meters. The Bureau's role consisted mainly of pointing 
out the need to industry and providing technical consultation. The 
uncertainty limit in all three instruments is 5 percent (0.25 dB) as 
compared to 10 percent previously. The need for improved accuracy in 
RF pulse power measurements has resulted from recent changes in 
DoD and FAA specifications for Airborne Tactical Air Navigation 
(TACAN) and radar altimeter equipment. These changes were de- 
signed to improve the accuracy and reliability of airborne systems vital 
to the safe operation of military and civilian aircraft. The new meters 
have been evaluated at NBS and are available for purchase on the 
open market. 

Microwave Region 

Development of Microwave Noise Standards — A new mechanism 
for describing and evaluating performance parameters in microwave 
systems has been developed. This description is based on "power 
equations" instead of microwave circuitry. As suggested by the termi- 
nology, the fundamental parameter is the net power flowing across 
the terminal surface; thus, the new technique requires only a single 
scalar parameter, while providing a systematic and unified approach 
to the mismatch error problem. It also incldes simplified techniques 
for evaluating mismatch corrections, and because the description is 
based on "terminal invariant" parameters, the uniform waveguide 
and precision connector requirement is eliminated for an important 
class of practical measurement problems. 

Development of Millimeter Wave Standards — The conventional 
microwave approach to component design begins to break down at mili- 
meter wavelengths because of difficulties in achieving precise dimen- 
sions and tolerances and because of unacceptable losses and limited 
power-handling capabilities. It is currently thought that development 
of standards at these wavelengths will require the use of electronic 
components based on quasi- optical principles. As part of a new NBS 
effort in the area, a circular polarizer and a turnstile junction were 
built and evaluated. Their design was based on an optical principle 
not previously applied to components at millimeter wavelengths. 
Successful operation of the components has broadened the base of tech- 
nology available for the development of millimeter wave standards. 

Precision Microwave Power Measuring System — Power is a funda- 
mental quantity in microwave equipment design and testing. Highly 
accurate measurements can now be made with new d-c substitution 
techniques using a bolometric detector in a bridge arrangement. This 

36 



system is an improvement over the original self-balancing d-c bridge 
developed at NBS in 1956 and used extensively by standards labora- 
tories throughout the country. The new system will find even wider 
acceptance because it permits improved accuracy at the field level. In 
addition, there is a reduction of cost by a factor of seven, and reduction 
of weight by a factor of twenty. The system, which is completely 
solid state, also functions as a precision power leveller, a 0-10 V differ- 
ential voltmeter, and an ultrastable 0-10 V power supply. This com- 
bination of features permits the measurement of r-f power levels 
of the order of 10 mW without accessory slidewire potentiometers or 
digital voltmeters. 

Josephson-Effect Studies — Experiments were undertaken to deter- 
mine the maximum frequency at which Josephson-effect oscillations 
could be observed in superconducting point contacts. Earlier work 
in this field was limited to photon energies below or near the energy 
gap of the superconductor, since it was generally believed that signifi- 
cantly higher frequencies would not be observable. Quite to the con- 
trary, oscillations were detected at frequencies as high at 8200 GHz — 
a photon energy of approximately 12 times the energy gap. These 
results are significant both for the theory of superconductivity and 
because they indicate that Josephson junctions may be useful as de- 
tectors, harmonic generators, mixers and spectrum analyzers in the 
infrared, where few other coherent devices are available. 

Photometric and Radiometric Quantities 

Effect of Lowering Size and Brightness on Color Discrimimation — ■ 
The ability to discriminate between colors becomes poorer when the 
brightness is lowered or the size of the target is decreased. The loss in 
color discriminability is more marked for blue-yellow differences than 
for red-green differences. This phenomenon has long been known in 
color signalling, such as in the railroading and lighthouse services, 
where it is generally understood that purple, blue and yellow can not 
safely be used for signal lights that must be identified at a distance. 
As the distance from the observer to the target is increased, the visual 
size of the target decreases, and a loss in color discriminability results. 
A study has been made of the relation between size and brightness for 
a given loss in discriminability. This study indicates that decreases in 
size of target can be compensated by increase in brightness. Con- 
versely, low levels of brightness can be compensated by an appropriate 
increase in target size. The appropriate increases were also determined 
and were found to be systematic. 

Theory of Perceived Size of Color Differences — Because of indus- 
trial need of a mathematical basis for setting color tolerances, several 
approximate measures of perceived size of color differences have been 
developed empirically. One of these is based on distance on the CIE 

37 



1960 UCS diagram, so-called because it was recommended by the In- 
ternational Commission on Illumination (CIE) in 1960 as yielding an 
approach to uniform chromaticity spacing. Current studies at NBS 
have shown that this diagram can be derived from the second stage of 
the Miiller theory of vision. This second stage treats normal vision as a 
combination of protanopic (yellow-blue) vision with tritanopic (red- 
green) vision. This view implies that the true measure of color dif- 
ference is not distance on the CIE 1960 UCS diagram, but rather the 
angles between the protanopic confusion lines on this diagram for 
amount of yellow-blue difference, and those between tritanopic for 
red-green. This theoretical measure checks out well for differences 
between the various colors of the spectrum, and is being checked now 
for other colors. 

The Ideal Lovibond Color System — The Lovibond System of red, 
yellow, and blue glasses has been used for many years for the grading 
of transparent materials. The color scales of the system were calibrated 
in arbitrary units with the three units related in such a way that for 
daylight illumination a combination of one unit each of the red, yellow, 
and blue glasses results in an approximately neutral filter. In 1962, 
ideal units of the three filters were defined and colorimetric coordi- 
nates were determined, in accord with the 1931 (International Com- 
mission on Illumination) standard observer and coordinate system, for 
multiples of the unit filters and various two-filter combinations of 
them. These 1962 determinations were made only for tungsten illumi- 
nation of the filters (Illuminant A). Calculations of the chromaticity 
coordinates have now been made of the same combinations of the unit 
filters, for daylight illumination (Illuminant C). In 1960 and in 1964, 
the CIE recommended the use of two transformations of the original 
1931 coordinate system yielding improved uniformity of spacing. The 
chrouiaticity data of the Lovibond System have now been computed 
for both Illuminants A and C, in terms of both the 1960 (u,v)- and the 
1964 (Z7*,F*,TF*) -transformations of the 1931 (X,Z,Z) -coordinate 
system. These tabulations enable convenient expression of uniform 
color tolerances in terms of Lovibond glasses. 

Spectroradiometric Photometry — A procedure has made it possible 
for the first time to calibrate with reasonable accuracy the lumen out- 
put of a light source of any spectral distribution by means of in- 
candescent standards. The method is based on a comparison of flux 
from the lamp to be tested with that from an incandescent standard 
at each wavelength interval of the visible spectrum. A set of 40 W 
cool-white fluorescent lamps was calibrated with this instrument and 
made available to the lamp industry through a commercial testing 
laboratory. An industry-wide intercomparison of 40 W cool-white and 
daylight fluorescent lamps was set up and preliminary results are now 
available. Although substantial progress has been made toward con- 

38 



sistent spectroradiometric measurements throughout the industry, 
further work will be necessary before the measurement system can be 
considered completely satisfactory. 

Standard Detectors for the Vacuum Ultraviolet — The investigation 
of the day-to-day reproducibility of the photoelectron yield of several 
materials — Au, W, A1 2 3 on Al, Co, Al — suitable for use as the cath- 
ode of a windowless diode has continued. Detectors of this type could 
serve as standards for wavelengths less than 105 nm, where durable 
window materials do not exist. Preliminary results indicate that cer- 
tain materials — A1 2 3 on Al, Au — under prescribed conditions of 
measurement and storage, exhibit reproducibilities of photoelectron 
yield of better than 5 percent. Windowed, evacuated diodes are being 
investigated for use at wavelengths longer than 105 nm. Early results 
indicate excellent stability of calibration — with reproducibility better 
than 5 percent — is possible in this region. 

Laser Power Measurements — Using a laser calorimeter with a timed 
shutter (developed at NBS for pulsed laser energy measurement), 
techniques have been developed to measure the average power of CW 
lasers in the wavelength range of 450.0 to 1060.0 nm. CW power- 
measuring devices may be intercompared with a ±4.0 percent accu- 
racy by using comparison techniques similar to pulsed energy meas- 
urements. Also, a power meter was developed which is capable of 
measuring the power of a 200 W CW C0 2 laser with an accuracy of 
±4 percent. The laser beam is absorbed in a hollow, blackened copper 
cone through which water flows at a known rate. The measured tem- 
perature rise and the rate of flow give the power of the laser. The 
range of the meter was estimated to be from 1 W to well over 10 kW ; 
however, NBS at present does not possess lasers with powers to test 
the full range of the meters. 

PHYSICAL PROPERTIES 

Approximately half of the activity within the Institute for Basic 
Standards is related to the measurement of physical properties of 
well-defined substances. The rapid growth of the physical sciences has 
provided scientists with many new techniques for measuring "old" 
physical properties and has made accessible many new ones. With new 
techniques it has been possible to increase the precision of measure- 
ment, provide the scientific community with a greater range of ref- 
erence data, and characterize certain processes more fully. Examples 
of these activities, drawn from current work, are given below. 

Atomic and Molecular Properties 

Radio Line Spectra of OH — During January and February of 
1968, precision measurements were made, of the radio line spectra of 

39 



two excited states of the OH molecule, at the request of Harvard radio 
astronomers. Current theories of the excitation conditions of inter- 
stellar OH gas involve these two states, and the Harvard astronomers 
were about to make a sky search for the corresponding line radiations, 
using the large radio telescope at the National Radio Astronomical 
Observatory at Greenbank, West Virginia. Provided with laboratory 
measurements accurate to within 1 ppm, the Harvard scientists tuned 
their telescope to the correct frequencies and were able to detect faint 
OH signals in a single night of observation. Without the NBS measure- 
ments, the search might have failed or might have required a great 
deal more telescope time and expense. 

Departure from Equilibrium in a Nitrogen Arc — Although previous 
studies of sources similar to the atmospheric nitrogen arc had not 
revealed departures from local thermodynamic equilibrium (LTE), 
the availability of improved experimental techniques made the 
reexamination of this source attractive. Absolute intensity measure- 
ments were made on various atomic and molecular spectroscopic fea- 
tures produced in an atmospheric-pressure nitrogen arc operating at 
temperatures from 5,000 to 15,000 K. The relationships among the 
intensities of these spectral features were then compared with the 
corresponding relationships among the upper-state populations in 
LTE in order to obtain optical transition probabilities and reveal 
departures from equilibrium. The data from the N i and N n lines were 
consistent with the existence of LTE above 11,000 K and recently pub- 
lished transition probabilities. On the other hand, no choice of transi- 
tion probabilities for N + 2 or N 2 bands resulted in agreement between 
the experimental data and LTE calculations below 10,000 K. 

Arc Measurement of Some Am Optical Transition Probabilities — 
In recent years, many efforts have been made to measure or calculate 
transition probabilities and related quantities for the strong lines in 
the visible spectrum of Ar n. While two recent sets of lifetime measure- 
ments show good agreement with each other, results derived from 
theoretical calculations and emission measurements exhibit disagree- 
ment as large as a factor of two. Emission measurements leading to the 
determination of more than 100 Am transition probabilities were 
made in the hope of reducing the uncertainty attached to some of 
these values. Measurements were made in a wall-stabilized, atmos- 
pheric-pressure argon arc and transition probabilities obtained using 
the generalized Fowler-Milne technique. Transition probabilities, 
having an estimated uncertainty of 10 percent for the best cases, for 
all lines of the 4s-4^> and Sd-Ap Ar n arrays lying below 7200 A. 
Where comparison with lifetime measurements was possible, the agree- 
ment was satisfactory. 

Vibration- Rotation Hamiltonian for Triatomic Molecules — Two 
conventional theoretical formalisms exist for the vibration-rotation 

40 



problem in triatomic molecules : one appropriate for linear molecules, 
having four vibrational and two rotational degrees of freedom; the 
other appropriate for bent molecules, having three vibrational and 
three rotational degrees of freedom. In the present work, a single, 
unified formalism was developed, applicable to both cases. The unified 
formalism has two vibrational and three rotational degrees of freedom. 
The remaining degree of freedom, corresponding to the bending vibra- 
tion, is singled out for special treatment. Among other things, an exact 
quantum mechanical vibration-rotation Hamiltonian was derived; a 
slightly modified fg matrix formalism for the stretching vibrations 
was introduced ; and the dependence of the rotational constant on the 
bending vibrational quantum number was determined. The formalism 
was applied to experimental data for HCN/DCN, H 2 0/D 2 0, and 
CsOH/CsOD. It displayed distinct advantages in the HCN/DCN case. 

Atomic Spectra — New energy levels have been found for atoms or 
ions of Tc, W, CI, Y, La, Pr, Pm, Tm, and Th. These theoretical calcu- 
lations have aided in the interpretation of many of these new levels, 
as well as in electron configurations in K, Cu, Zn, Ag, Cd, and Tl. Such 
analyses of optical spectra are useful for interpreting astronomical 
and plasma spectra, predicting thermodynamic and chemical proper- 
ties, and for solid state and atomic physics. 

Accurate Reference Wavelengths in the Optical Region — New 
measurements and application of the Eitz principle have yielded 1,570 
improved wavelengths in the thorium spectrum from 2600 A to 13,000 
A. The uncertainty ranges from 0.0002 A for the shorter wavelengths 
to 0.002 A at the long wavelengths. Similar work gave over 500 wave- 
lengths for krypton 86 (the spectrum containing the primary standard 
of length), accurate to ± 0.0001 A at the short wavelengths (3400 A) 
and to ±0.01 A at the longest wavelengths (4/xm) . A list of almost 2,200 
vacuum-ultraviolet wavelengths accurate to ±0.002 A or better has 
been compiled for the region 300-2000 A. This list contains many lines 
(belonging to frequently observed spectra) measured at NBS to 
±0.0005 A. 

Torsional and Ring Strain Forces in Molecules — Studies have re- 
cently been made to determine the structures of a series of small, ring- 
shaped molecules: silacyclopentane ; 2,5-dihydiothiophene; 2,3-di- 
hydiothiophene ; silacyclopentane; and cyclopentene oxide. These 
molecules are of particular interest to theoretical chemists because the 
precise shape of the ring is determined by a delicate balance between 
ring strain forces, which tend to make the ring planar, and torsional 
forces between hydrogen atoms attached to adjacent carbon atoms. The 
torsional forces act to pucker the ring into a nonplanar conformation. 
These two types of forces are also important for a number of large bio- 
logically active molecules. Before such large molecules can be under- 

41 



stood, however, we must be able to understand small molecules, which 
are easier to study. By studying certain low-frequency vibrations of 
these molecules by far infrared or by microwave techniques, the details 
of the forces controlling the ring structure in these molecules can be 
determined. 

Plane Grating Spectrograph — A new plane grating spectrograph 
combining speed with high resolution has been constructed. It is being 
used to photograph spectra of atoms and molecules with resolving 
powers (greater than 5 X 10 5 ) not previously available in grating in- 
struments at NBS. The general optical design is a modification of the 
two-mirror Czerny -Turner arrangement with a focal length of 3.34 m. 
The line definition was improved by increasing the focal length of the 
collimating mirror and positioning the slit very close to the photo- 
graphic plate. 

Transition Probability Measurements in the Neutral Argon Spec- 
trum — Numerous recent determinations of transition probabilities of 
neutral argon are indicative of the importance of this noble gas in 
high-temperature technology. Nevertheless, serious discrepancies be- 
tween the various experimental and theoretical results have remained. 
Therefore, two independent measurements and an extensive analysis of 
all other work on the argon spectrum have been performed to clarify 
this situation. The two experiments were, first, lifetime determinations 
of the prominent 5p states with a delayed coincidence apparatus, and, 
second, emission measurements of 80 infrared lines with a wall-stabi- 
lized arc. A number of the transitions measured with the arc originate 
from the 5p states so that they could be linked up with the lifetime 
results as well as some other arc data obtained at NBS to determine 
the internal consistency of all measured values. With this combined 
effort a reliable set of transition probabilities for the more prominent 
argon lines has been established. 

Photodetachment Studies — Photodetachment studies on the ion 
(H 2 0) OH" have shown that this ion may play an important role in 
controlling electron densities in the D region of the earth's upper atmos- 
phere and lower ionosphere. In this work, photodetachment has been 
observed to take place only in the ultraviolet and deep violet region of 
the spectrum : most visible radiation will not detach the most weakly 
bound electron from this ion. The observed spectrum indicates that 
the H 2 — OH - bond is relatively weak (<1 eV). Thus the relatively 
large photodetachment cross section (<10 -17 cm 2 ) at short wavelengths 
may be accompanied by a large photodissociation cross section in the 
infrared region. 

Photodetachment studies of S~ have provided for the first time 
an absolute cross section 2 X 10 17_ cm 2 , and a more precise value of the 
electron affinity, 2.095 ± 0.015 eV. This work also indicates that the 
previous application of threshold behavior theory is probably less 
exact than had been generally believed. 

42 



Compilation of Volume II of Critically Evaluated Data in Atomic 
Transition Probabilities {Elements Na through Ca) — The critical 
evaluation of atomic transition probability data for the second 10 
elements of the periodic system (Na through Ca) has been completed 
and the tables have been published as part of the NSRDS-NBS series. 
Numerical "best" values for approximately 5,000 transitions, both 
allowed and forbidden, have been tabulated and for each value an 
estimated uncertainty has been given. The bulk of the data is estimated 
to be accurate within 50 percent. The best accuracy is 3 percent for the 
famous sodium D- lines. The compilation contains many original data 
which were obtained by numerical applications of the coulomb 
approximation and by utilizing the systematic trends of oscillator 
strengths within isoelectronic sequences. 

Continuous Emission from a Hydrogen Plasma — The continuous 
emission from a hydrogen arc plasma has been extensively investigated 
theoretically as well as experimentally. The continuum studies are 
of considerable interest primarily because the hydrogen continuum 
has great potential to become one of the principal spectral radiation 
standards in the near ultraviolet and vacuum ultraviolet where no 
established radiation standard exists as yet. Computer calculations 
of the continuous emission have been performed over an extended 
range of temperature encountered in arc operations. The contribu- 
tions from the hydrogen negative ion (H~) and the hydrogen molecu- 
lar ion (H 2 + ) have been included, using recently calculated absorption 
coefficients, and the contributions of the extended line wings of the 
hydrogen lines have been considered for the first time. Intensity 
measurements with a pure hydrogen arc carried out at 13,000 K show 
that the relative spectral continuum distribution in the observed 
range from 2,800 to 6,000 A follows the calculations within a few 
percent. However, the measured continuum is stronger by about 15 
percent than the calculated one on an absolute scale. Some of the 
likely causes of this disagreement, like small deviations from thermo- 
dynamic equilibrium in the arc, are currently being investigated. 

Microwave Spectra of Free Radicals — The microwave spectra of 
BrO and SF 2 have been observed for the first time. Transitions from 
the 2 n 3/2 state in BrO were detected, but not from the 2 n 1/2 state. The 
observed data for this molecule led to a rotational constant, hyperfine 
parameters, and nuclear quadrupole constants. Observation of the 
spectrum of SF 2 was of particular interest, since the chemical litera- 
ture contains meager and conflicting reports of attempts to synthesize 
the molecule. The observed data for this molecule led to rotational 
constants, a dipole moment, and a prediction (with the help of a 
complete centrifugal distortion analysis) of the molecular force con- 
stants and infrared spectrum. 



375-572—70- 



43 



Analysis of Optical and Electron Scattering Data — A procedure 
has been developed to improve the analysis of optical- and inelastic- 
electron-scattering data. A least-squares computer program has been 
used to check the mutual consistency of models for the complex 
frequency- dependent dielectric constant (for example, the Drude- 
Lorentz model) and of different types of experimental data (for 
example, reflectance and inelastic electron scattering cross sections) 
for a number of elements (Al, Cu, Be, Ge, Sb, Bi, Na, and K) within 
the accuracy of measurement. The model parameters from satisfactory 
fits can be used for the identification of structure for comparison 
with theory, and to derive optical constants. In deriving optical con- 
stants from ultraviolet reflectance measurements, for example, the 
jDresent approach obviates the necessity for arbitrary extrapolations 
of normal -incidence data, and better precision can be obtained than 
in the conventional analyses of data obtained at multiple angles of 
incidence. 

Laser Electron Paramagnetic Resonance — A new technique involv- 
ing an HCN laser in EPK was developed and given the name LEPK 
(Laser Electron Paramagnetic Eesonance). This technique involves 
focusing the beam of the HCN laser on a small hole in the mirror of 
a Fabry-Perot interferometer centered in a uniform external magnetic 
field. The radiation is monitored by a Golay cell through a small hole 
in the opposite side of the interferometer. The output of the cell 
is connected to a 13.5 Hz phase detector referenced to the modula- 
tion of the magnetic field. A few torr of oxygen gas is placed in the 
Fabry-Perot, and the magnetic field is swept. Any absorption of 
energy by the oxygen gas is detected by the Golay cell. Using this 
technique, five lines in oxygen were observed. Considerable improve- 



iKIM^W*€SP»ijSS'i%*#t*J5 ; 5SS 



I 



WKc 




Sample cell used in laser EPR studies of oxygen (12 lines observed) and N0 2 
(over 200 Unes observed). 



44 



ment was achieved by making the oxygen absorption cell part of 
the laser and employing a Brewster window between the HCN and 
oxygen to determine the polarization of the radiation. With the 
improved sensitivity, a total of 12 lines has been observed and 
identified, and further improvements are planned. The spectrum of 
N0 2 is also being taken ; thus far, over 200 lines have been observed. 

Electron Density Measurements — The abnormal negative glow 
plasma in helium has been adapted for a thorough investigation of the 
microwave cavity technique used to measure the electron density in 
plasmas. This negative glow plasma, in combination with a low fre- 
quency microwave cavity, was used for experimental and theoretical 
investigations of the influence of longitudinal modes on the microwave 
measurements. A double perturbation technique allows for evaluation 
of the microwave field within the plasma and an extension of the 
cavity measurements beyond the limits of the simple perturbation 
method. Data indicate that use of the microwave technique, as inter- 
preted by the simple perturbation theory, is more limited than com- 
monly thought, due to the presence of excited longitudinal modes not 
accounted for by the theory. The double perturbation technique has 
in some situations extended the limits for the measurable electron 
density by about 1-2 orders of magnitude. 

Heat Pipe Oven — A new, well-defined metal vapor device called 
the heat pipe oven has been developed for spectroscopic measurement- 
Based on a heat conductive element first developed at the Los Alamos 
Scientific Laboratories, the oven continuously generates homogeneous 
vapors of well-defined temperature, pressure, and optical path length. 
All three parameters can be measured directly with high accuracy. The 
vapor is confined by inert gas boundaries which remove the window 
problem and allow a direct pressure measurement without relying on 
vapor pressure curves. As such, the heat pipe oven is suitable for use 
in connection with vacuum UV spectrometers. It has already been 
used successfully in a number of different spectroscopic measurements 
(line broadening, transition probabilities, cross sections, etc.) and has 
been applied to the generation of metal vapor plasmas. 

Line Broadening Theory — A new theoretical treatment of spectral 
line shapes emitted by plasmas has been developed. This approach, 
called the unified theory, provides the first line-shape theory capable 
of describing a line profile from the line center to the quasi-static 
wings. Calculations of the Lyman a line of hydrogen have been made 
and compared with experimental results and other theories. The 
calculations provide the first accurate description of the transition 
from Markovian to non-Markovian electron broadening. This approach 
should provide a strong foundation on which further investigations 
of line shape phenomena can be based. 

45 




A modified heat-pipe oven (left) is here being used in spectroscopic investigations. 

Electron Impact Cross-Section Data Bank — A data bank containing 
evaluated experimental cross sections for low-energy electron impact 
on atoms and small molecules is now active. Data are gathered on a 
regular basis from the current scientific literature. Graphical display 
on microfilm can be prepared from the cathode ray tube used as a 
computer output device. This system will allow fast resopnse to re- 
quests for the latest evaluated cross-section data and makes possible 
the updating of hard copy on a regular basis. 

Dissociative Processes of Simple Molecules — An apparatus has been 
constructed to measure the angular and energy distributions of ener- 
getic ions produced by electron impact on molecules. Ion counting is 
used so that the processes can be observed near threshold where cross 
sections are small. Initial work on the energy and angular distribution 
of protons from H 2 has yielded a direct measurement of the momentum 
transferred to the molecule center of mass in the ionization process. 
This is the first such measurement and will provide theorists interested 
in the ionization process near threshold with some valuable checks 
on their theories. This work has also shown that the angular distribu- 



46 



tion of protons near threshold is not a pure cosine-squared distribu- 
tion, but contains an isotropic part which may be due to autoionizing 
states of H 2 . After subtracting out the isotropic part, the resulting 
angular distribution seems to fit a more complicated function as pre- 
dicted in a recent calculation. 

Dissociation Energy of Li 2 from Laser-Excited Fluorescene — A new 
value for the dissociation energy (bond strength) of the Li 2 molecule 
has been established. This was accomplished by analyzing the fluores- 
cence excited in the 6 Li 2 , 6 Li 7 Li and 7 Li 2 molecules by various lines of 
the argon ion laser. The fluorescent light was dispersed using a % -meter 
spectrometer. A Birge-Sponer extrapolation of the G(v) values gave 
D ° = 1.026 ±0.006 eV. This value, combined with the dissociation limit 
of the upper state previously determined by Loomis and Nusbaum, 
proves that there is a potential maximum of about 0.12 eV above the 
asymptote of the potential curve for the Li 2 B 1 U U state. Experimental 
determination of the magnitude of the potential barrier for this funda- 
mental molecule should serve as a useful check on various theoretical 
calculations of the interactions between atoms at intermediate 
distances. 

Solid State Properties 

Thermal Expansion of Platinum — The linear thermal expansion of 
two specimens of platinum has been measured with a high-precision 
optical comparator between 1000 and 1900 K. These data are believed 
to be accurate to 30 ppm for this material in the hi^h-temperature 
range and will be very useful since platinum is widely used as a ref- 
erence material for calibrating dilatometers and x-ray diffraction 
equipment. 

Photoelectron Emission from Tungsten in the Vacuum Ultraviolet — 
Studies of the effects of adsorbed gases on the photoelectron emission 
from tungsten have shown the electron yield to be very sensitive to 
even partial monolayer coverages. Over a range of photon energies 
from 7.7 to 21.2 eV, each of the gases H 2 , N 2 , 2 , CO, C0 2 , NH 3 , and 
H 2 produced specific yield changes which were dependent upon the 
species and quantity of gas adsorbed. The behavior of the electron 
yield during adsorption can be qualitatively correlated with work 
function changes, and also offers evidence for the appearance of addi- 
tional electron emission produced by photoionization of the adsorbed 
gas. 

Baseband Pulse Delay Lines — A miniature 50-O superconducting 
coaxial line (80 feet long, Nb inner conductor 0.01"O.D., Pb outer con- 
ductor 0.034" I.D., PTFE dielectric) has been analyzed in terms of 
the complete Bardeen-Cooper-Schrieffer (BOS) theory of supercon- 
ductivity. The results have been compared with those based on the 

47 



two-fluid superconductivity model. The surface impedance of both 
superconductors, the line attenuation, and the picosecond time domain 
step responses have been calculated for a temperature of 4.24 K. Pre- 
liminary results indicate that with appropriate parameter values, the 
more tractable two-fluid model is adequate for engineering design con- 
siderations up to and including microwave frequencies. For higher 
frequencies, i.e., energies approaching or beyond the BCS energy gap, 
the complete BCS theory is required. 

Low-Temperature Thermal Expansion — The low-temperature 
thermal expansion of over 30 aluminum, nickel, copper, and iron-base 
alloys was measured from liquid hydrogen temperature (20 K) to 
room temperature. Both the thermal contraction from room tempera- 
ture and the thermal expansion coefficient were tabulated as a function 
of temperature. Comparison of similar alloys and alloy conditions led 
to the general conclusions that: (a) relatively large changes in com- 
position are required to produce significant changes in thermal expan- 
sion, (b) thermal treatment or condition has little effect except when 
it produces a basic structure change, and (c) the thermal expansion 
coefficient at room temperature is a good indicator of the total length 
change that occurs as alloys are cooled. 

Improved Superconductive Tunnel Junctions — A new method of 
fabricating tunnel junctions between superconductive niobium and 
lead films has been developed. The method consists of condensing the 
products of a glow discharge onto the surface of a cold (80 K) niobium 
film, followed by a thermal cycle and deposition of the lead film. This 
method gives a very high yield (~60%) of tunnel junctions with very 
low leakage current. After coating with a plastic layer to protect the 
film, these junctions become very rugged. They may be stored at 
ambient temperature, exposed to the atmosphere for many months, 
and subjected for many hundreds of cycles to a low temperature with- 
out detectable deterioration. They represent a significant step towards 
the fabrication of permanent instruments employing the Josephson 
effect. 

Development of Simper-Purity Aluminum — Design and construction 
of cryogenic aluminum magnets has been hindered in the past by the 
lack of large amounts of high-purity aluminum. Two years ago the 
highest purity available (99.9999) had residual resistance ratios of 
only 2,000 to 4,000. Now, through cooperation between NBS and in- 
dustry, aluminum of the highest known purity, having residual re- 
sistance ratios of up to 45,000, has been produced. It is expected to be 
extremely valuable in physical and mechanical property measure- 
ments, as well as for potential use in magnets and other commercial 
applications. 

48 



Thermodynamic and Transport Properties 

Determination of the Second Virial Coefficients and Intermolecular 
Potential for Several Important Gases — Methods developed for the 
optimum determination of virial coefficients and intermolecular poten- 
tial functions from experimental data have been applied to the litera- 
ture for the 14 important gases ( Ar, Xe, Kr, He, H 2 , N 2 , Air, Ne, 2 , 
D 2 , H 2 0, D 2 0, CH 4 , C0 2 ) . Tables of second virial coefficients and their 
first and second derivatives as well as intermolecular potential param- 
eters, and third virials have been produced. These second virial coeffi- 
cients and their derivatives are sufficient for the calculation of the 
real-gas corrections to the ideal-gas equation of state in many technical 
applications. The intermolecular potential functions can be used as 
input data in a variety of microscopic theories for macroscopic quanti- 
ties. These tables represent a considerable improvement over those 
generally available previously. 

Precise Experimental Determination of the Vapor Pressure of C0 2 
to Within Several Hundredths of a Degree of the Critical Point — The 
vapor pressure of C0 2 has been measured with a temperature precision 
of 0.001° C and a pressure precision of 0.001 bar to within 0.001° C 
of the critical point. The data have been fitted to a nonanalytic equation 
consistent with the scaling-law approach. The usual analytic vapor 
pressure equation is based on the Clausius-Clapeyron equation, and 
contains the assumption that the liquid specific volume can be neglected 
with respect to the vapor specific volume, an assumption clearly in 
error at the critical point where both volumes are equal ; thus, its fit 
exhibits systematic deviations near the critical point. The new equa- 
tion produces a fit with a standard error an order of magnitude 
less than that of the analytic equation, and no systematic trend in its 
deviations. 

Bose-Einstein Condensation — The condensation of an ideal Bose- 
Einstein system was studied using an approach in which the Bose 
transition acquires a very close resemblance to the second-order tran- 
sitions about the liquid-vapor and magnetic critical points. The system 
exhibits an appropriate macroscopic order parameter related to the 
conjugate field through an ordered sequence of terms in reduced 
thermodynamic variables. In the vicinity of the transition, the equa- 
tion of state takes on the homogeneous functional form predicted by 
the scaling hypothesis and exhibits a power-law behavior with non- 
classical exponents. The various ordered correlation functions 
(thermal expectation value for the various ordered products of Boson 
field operators) were determined and used to demonstrate the existence 
of a "critical eigenvector" conjectured by Green as a universal feature 
of critical points. An extension of certain properties of this simple 

49 



model lias also proven useful in understanding the hydrodynamics of 
a superfluid condensate. 

Determination of the Sensitivity of Thermodynamic and Transport 
Properties to the Intermolecular Potential Function — The simultane- 
ous fit of equilibrium and transport properties has been assumed to be 
a particularly sensitive method for the determination of potential 
functions, as has the isotopic thermal diffusion ratio. Both have been 
examined for their inherent sensitivity to the potential function. 
Kesults reinforce those obtained for the individual properties and 
show that no new information can be obtained, in principle, from the 
requirement of a simultaneous fit to pairs of properties. A method for 
the testing of a functional form of an intermolecular potential func- 
tion by the simultaneous fit pairs of properties was developed. 

The isotopic thermal diffusion factor has never been properly studied 
because of the large uncertainties present in such data. It has now 
been confirmed that the isotopic thermal diffusion factor can be a very 
sensitive probe of the potential function provided measurements are 
made at temperatures outside an insensitive temperature range. Un- 
fortunately much existing data were taken precisely at temperatures 
inside this insensitive range. The experimenter can now avoid such 
design errors in the future by choosing temperatures consistent with 
our results. The insensitive temperature range, 0.6<T/T B <1.2 where 
T B is the Boyle temperature, was found to be essentially that found 
for other transport properties previously studied. 

Analysis of PVT Data Obtained With Burnett Apparatus — In 
1936, Burnett described a simplified technique for the measurement 
of the isothermal compressibility factor of a gas. The parameters 
necessary for this method are pressure and temperature, eliminating 
the troublesome volume measurement; however, a nonlinear statis- 
tical problem must be solved to evaluate the compressibility factor as 
a function of pressure. Many different data-reduction schemes have 
been developed for the evaluation of the virial coefficients and the 
compressibility factor, each differing in its approach to uncertainties 
involved. A meeting on the Burnett data-reducing problem was held 
at NBS, focusing on particular problem areas, and resulting in close 
cooperation among several laboratories. A round-robin problem was 
designed and circulated, and the comparison of the various data 
analyses is being used to define the areas of disagreement. This ap- 
proach, established as a result of the meeting, will permit increased 
use of an experimentally simple method. 

Development of a Method for Optimizing the Coefficients Deter- 
mined from Measured Data Fitted to a Power Series for an Experi- 
ment of a Given Precision — In calculating the coefficients of a power 
series fitted to experimental data, several factors besides experimental 
precision affect the standard error of these coefficients. Using the prin- 

50 



ciples of statistical analysis, the effects of factors such as interval 
size, extrapolation, number, relative weight, and distribution of ex- 
perimental points were studied by high-speed computer experiments. 
On this basis it was determined how to adjust these various factors 
to minimize the standard error for a given experimental precision. 
For the particular case of gas PVT data, a density expansion is pos- 
sible and approximate theoretical knowledge of the first five coeffi- 
cients is available. This allowed for the formulation of experimental 
conditions (other than improved precision) leading to a decreased 
standard error in one or more of the first four coefficients. 

Critical Phenomena in Binary Liquid Mixtures — To study critical 
phenomena in binary liquid mixtures the system 3-methylpentane- 
nitroethane was selected. The refractive indexes of the liquid compo- 
nents of this system are such as to minimize multiple scattering in 
studying critical opalescence. Experiments were carried out to deter- 
mine the intensity of scattered light, the curve of coexisting concen- 
trations and the behavior of the surface tension as a function of 
temperature. 

Scaling-Law Analysis — A systematic review of the experimental 
evidence for the validity of the scaling hypothesis has been completed 
using the available data in the critical region for a number of systems. 
An extension of the previous work on fluids, and a careful analysis of 
several ferromagnets, have shown the scaling ideas to be consistent. 
A closed-form equation of state based upon the scaling laws has been 
suggested to relate the appropriate thermodynamic quantities (for 
fluids — chemical potential, density, and temperature, for ferromag- 
nets — internal magnetic field, net magnetization and temperature). 
Agreement between the proposed form and the experimental data 
shows that the equation of state is satisfactory within the entire critical 
region. 

Light Scattering — The frequency spectrum of light scattered by 
temperature, pressure and concentration fluctuations in a binary liquid 
mixture was obtained using the linearized hydrodynamic equations. 
The theory indicates that light-scattering measurements provide an 
attractive means of measuring binary diffusion coefficients, as no 
gradients are imposed on the system. 

Molecular Motion in Solids at Low Temperatures — Recent heat- 
capacity measurements on deuteromethane crystals have demonstrated 
that rapid transitions are taking place between the equivalent or 
nearly equivalent orientations of the molecules at temperatures well 
below 1 K. In addition, conversion between the different nuclear-spin 
states of the molecule accompanies the reorientation process. Similar 
behavior is well known in solid H 2 and D 2 , but it has long been thought 
that such processes were "frozen out" at such low temperatures in all 
other solids. The present results at 0.3 K show that this is not neces- 
sarily the case in simple molecular crystals. 

51 



High-Temperature Heat Capacity Standard — Over 20 years ago, 
NBS proposed synthetic sapphire (pure poly crystalline a— A1 2 3 ) as 
a highly suitable heat-capacity standard for intercom/paring calorim- 
eters in different laboratories from below room temperature to near 
its melting point (above 2300 K). The heat capacity measurements 
subsequently made by NBS from 15 to 1173 K have been the standard 
reference since that time. A new sample of this substance has recently 
been prepared as a Standard Reference Material, and precise calori- 
metric measurements from 273 to above 2000 K were performed on 
several specimens. The results, using apparatus of improved precision, 
match the earlier values over the entire range of overlap, as well as 
joining the previous measurements below 273 K. 

In addition to providing a new, carefully characterized sample, this 
recent work inf erentially has revalidated the older samples still in use. 
Technology of Liquid Helium — A publication on the "Technology 
of Liquid Helium" was edited and partially written by members of the 
NBS staff. This monograph brings together articles by 16 noted 
authorities in cryogenic technology. Individual chapters cover a full 
spectrum of subjects including Resources, Production and Conserva- 
tion, Properties, Techniques for Liquefaction and Refrigeration, Stor- 
age and Handling, Safety, Cryoelectronics, and Applications for 
cryopumping, superconductivity, bubble chambers, and missile and 
space systems. 

Thermal Conductivity of Gaseous and Liquid Hydrogen — The 
thermal conductivity of normal and parahydrogen has been measured 
at temperatures from 17 to 200 K and at pressures to 150 atm (15MN/ 
m 2 ). These measurements have filled a large gap in the knowledge of 
this property ; they are the first comprehensive measurements on the 
compressed gas and liquid at temperatures below 78 K. The behavior of 
the thermal conductivity of hydrogen appears to be similar to that 
of other fluids except that the temperature dependence of the con- 
ductivity of the liquid at constant density is much larger than that 
of most other fluids except helium. These measurements complete a 
ten-year, NASA-supported program on the physical properties of 
parahydrogen at low temperatures. 

Helium Heat Transfer — A 3-year program has been initiated to 
supply needed information on helium heat transfer. The technology of 
superconducting materials and cryogenically cooled high purity sub- 
stances has reached a point where their use as electrical-current con- 
ductors is being planned into practical systems. But lack of reliable 
information on helium heat transfer is a serious obstacle to the develop- 
ment of industrial devices. This new NBS program is funded by the 
Atomic Energy Commission and monitored by a committee with rep- 
resentatives from all of the major AEC laboratories, NASA, DOD, 
and NBS. It will include the generation of property values for con- 

52 



ductivity and viscosity of Helium I. Additionally, studies will be car- 
ried out analytically and experimentally to determine the heat-transfer 
coefficients for supercritical Helium I and the heat transport through 
Helium II as well as the interface between Helium II and solid ma- 
terials (Kapitza conductance). 

Thermodynamic Properties of Argon — The thermodynamic prop- 
erties of argon have been calculated from an equation of state which 
was fitted to experimental P-p-T data from the world literature. These 
calculations are one result of a study which was conducted over a 
period of several years and included exhaustive analysis of existing 
experimental data by both statistical and thermodynamic theory. The 




He 3 -He 4 dilution refrigerator produces temperatures below 0.1 K. Refrigeration 
is produced in a chamber inside a coil (arrow) used to measure the tempera- 
ture. Suspended from the chamber are two devices to be tested — a Josephson- 
junotion thermometer on the disc and a heat exchanger to the left. In use 
the refrigerator is surrounded by a vacuum space and several thermal shields. 

53 



results of this effort are described in an NBS publication containing 
tabular values of density, internal energy, enthalpy, and entropy. 
Diagrams of the specific heats, compressibility factor, and thermo- 
dynamic properties are included. 

Saturated Liquid Densities of Oxygen, Nitrogen, Argon, and Para- 
hydrogen — Standarized density data were prepared for the saturated 
liquids of four commercially important gases — oxygen, nitrogen, ar- 
gon, and parahydrogen. Users such as the Compressed Gas Associa- 
tion, the Department of the Air Force, and NASA require consistent 
and accurate values for the physical properties of these gases in order 
to achieve consistency in cost determinations. The State of California 
has used extracted tables in their code (law) for cryogenic measuring- 
devices. The Compressed Gas Association is reissuing their pamphlet 
P-6 using these values as the data base. 

He 3 -He 4 Dilution Refrigeration — A refrigerator operating on the 
He 3 -He 4 dilution principle has been designed and constructed utilizing 
a previously prepared tabulation of the thermodynamic properties of 
He 3 -He 4 solutions. This refrigerator has achieved a continuous tem- 
perature of 0.020 K and a lowest temperature of 0.013 K. It was re- 
cently installed in a shielded room to minimize electromagnetic effects 
on sensitive instrumentation. Plans call for the experimental evalua- 
tion of transport and thermodynamic properties of He 3 -He 4 solutions, 
determination of the physical properties of solids, and investigation of 
devices such as the Josephson junction thermometer. 

MECHANICAL PROPERTIES 

Classical Theory of Sound Propagation — An analysis of the equa- 
tion customarily assumed to describe the propagation of acoustic 
waves in a fluid continuum considering viscosity, compressibility, and 
heat conduction has been carried out, calculating the transient as well 
as the steady-state response predicted by these equations. A bounded 
solution requires that an inequality involving the bulk and shear 
viscosity, the specific heats at constant volume and constant pressure, 
and the thermal conductivity be satisfied. This inequality appears to 
be obeyed for all fluids except the molten metals, including mercury, 
and possibly helium II. This failure probably indicates that some of 
the assumptions made in deriving the initial equation are inadequate 
when thermal effects are more prominent than viscous effects. The 
common assumption that the velocity of sound in an inviscid fluid 
varies continuously with increasing frequency from adiabatic to iso- 
thermal values was shown to be invalid except for one very special 
case. 

Absolute Viscosity of Water — The rheology section completed an 
extended program in which measurements of the viscosity of a liquid 

54 



using two independent absolute techniques were compared. Ordinarily, 
measurements of viscosity yield only the viscosity of various 
liquids and reference is H 2 at 20 °C and 1 atmosphere. These can 
quite easily be made to 0.1 percent, but absolute measurements on any 
liquid to better than about 1.0 percent are difficult and are seldom 
undertaken. Moreover, most previous measurements have utilized flow 
through a capillary and involved certain end effects which may cause 
undetected systematic error. The NBS measurements involved two 
quite different types of flow, one inside an oscillating sphere, the 
second through a channel whose dimensions could be established 
very accurately. The results of these two measurements differ by 0.4 
percent. By chance they bracket the value of H 2 previously accepted 
as the most reliable. Hence, the results of this program do not change 
previously accepted values for viscosity, but do for the first time 
provide a basis for assigning an accuracy (of ±0.2 percent) to all 
such measurements. 

APPLIED MATHEMATICS 

The Institute for Basic Standards conducts a program in applied 
mathematics and statistics to meet varied needs in the development of 
new measurement techniques and in the evaluation of the results of 
measurement. The level of the mathematics involved makes it essential 
to conduct fundamental mathematics research on a fairly broad scale. 

Computer-Controlled Scanning Microscope and Image Processor — 
A system has been designed and constructed for biological image- 
processing using a scanning microscope and several remote time-shar- 
ing computers. The scanning microscope, which is under computer 
control, measures the light flux passing through a specimen on the 
stage of a microscope. This measurement is made to one part in 256 
for each point in square array of 256 by 256 points which is super- 
imposed on the image appearing in the microscope. At present, the 
image thus quantized is recorded on magnetic tape for processing by 
a remote computer. 

The remote computers (a PDP-10 and an ANFSQ32) are used to 
analyze the structure of the biological objects recorded on the tape. 
The morphological structure of such biological objects as nerve cells 
and blood cells is obtained by having the computer decompose the 
image into its component parts and then attempt to reconstruct the 
object according to known rules governing the prescribed shape of 
the whole object. This type of articular analysis is done in the pro- 
gramming language "LISP." This language provides facilities for 
the manipulation of partial orderings (tree structures) which repre- 
sent the results of the image analysis. 

Through the use of the interactive feature of the time-sharing 
computers, it is possible for a biologist to develop reasonably elaborate 

55 



criteria for the recognition and analysis of the objects portrayed in the 
microscope image because as he develops these criteria he can see their 
consequences immediately and refine or correct them at once. Cur- 
rently, biologists are using this system to develop criteria for the 
analysis of the cytoarchitecture and morphology of central-nervous- 
system tissue, and for the study of autoradiographs of white blood 
cells as part of a study of cell kinetics. 

Numerical Analysis — A method for computing absolute error 
bounds in terms of various matrix norms for the output of any matrix 
inversion program was refined and incorporated into an existing com- 
puter program. Error analysis for the stationary-phase method of 
approximation was completed. An explicit expression for the error 
term was found for the general case. Useful applications were made 
in the approximation by asymptotic expansions of Bessel and other 
special functions of mathematical physics. The method of Chester, 
Friedman, and Ursell for approximating definite integrals with 
nearly coincident saddle-points was extended. 

FORTRAN Version of OMNITAB— The Bureau's highly user- 
oriented, genera] -purpose computer program, OMNITAB, has been 
rewritten in ASA FOKTKAN in order to make it as nearly machine- 
independent as possible. The program is being used successfully by 
scientists in numerous university, industrial, and government labora- 
tories on at least five different makes of computers. OMNITAB is 
used easily, quickly, and effectively by nonprogrammers for the cal- 
culation of tables of functions, for solutions of nonlinear equations, 
for curve fitting, and for statistical and numerical analysis of data. 
The program reads data in free-field format and executes instructions 
written in the form of simple English sentences. It is particularly 
well-suited for exploratory non-routine data analysis. 

Evaluation of Linear Least Squares Computer Programs — Two 
linear least squares test problems, both fifth-degree polynomials, have 
been run on more than twenty different computer programs in order 
to assess their numerical accuracy. Among the programs tested were 
representatives from various widely used statistical packages. Some 
of these were highly inaccurate in comparison to programs (such as 
NBS's OKTHO) that have been available for many years. A number 
of programs yielded results (coefficients) that were completely errone- 
ous, containing not even one correct significant digit. The tests were 
run on several different computers, in double as well as single preci- 
sion. It was found that those programs using orthogonal Householder 
transformations or Gram-Schmidt orthonormalization were much 
more accurate than those using elimination algorithms. Programs 
using orthogonal polynomials (suitable only for polynomial fits) also 
proved to be superior to those using elimination algorithms. 

Selected Papers on Statistical Concepts and Procedures — The Bu- 

56 



reau has published Volume I, Statistical Concepts and Procedures, of 
the twelve-volume NBS Special Publication 300, Precision Measure- 
ment and Calibration. This 441-page volume collects, for easy refer- 
ence, reprints of 40 selected articles on topics of special importance to 
metrologists. Each of six sections of the volume is preceded by a 
foreword pointing up the purpose for which the papers are included. 
Section titles are: (1) The measurement process, precision, systematic 
error, and accuracy ; (2) Design of experiments in calibration ; (3) In- 
terlaboratory test; (4) Functional relationships; (5) Statistical 
treatment of measurement data; (6) Miscellaneous topics. A list of 
references and an extensive subject index are provided. 

Finding Shortest Paths— In analyses of transport or communica- 
tions networks, it is frequently assumed that a traveller will select (or a 
unit of traffic will be routed along) a path which is "shortest" with 
respect to time, cost, or some other pertinent feature. Because a single 
applied study may require solving a great many shortest-path prob- 
lems, perhaps involving large networks, it is important to classify 
and experiment with various solution methods so as to know which 
techniques may be best suited to particular situations. Following 
preparation of a computationally oriented survey giving flow-charts 
and descriptions of over 20 variants, the Bureau conducted compara- 
tive tests of the more promising methods on a variety of real and 
"generated" networks. 

Scheduling Algorithms— Proper scheduling in a transportation 
system increases the public service derivable from a given investment 
in fleet and facilities. Workers on mathematical scheduling methods 
have tended to ignore the important interactions between patronage 
and schedules. The Burau has developed operational algorithms for 
near-linear ("acyclic") networks which account for this interaction. 
Though focused on intercity rail movement, the technique should be 
valuable for other modes and for urban transport as well. In addition, 
Bureau-supported work has yielded the first rigorous treatment of 
jointly optimal scheduling for "express" and "local" service. 

TECHNICAL ASSISTANCE TO OTHERS 

Advisory and Consulting Services 

Location of Cargo-Consolidation Centers — The development of a 
system of inland consolidation centers for marine cargo has been 
suggested as a means of improving the efficiency of U.S. international 
trade activities. As part of a project conducted jointly with the Tech- 
nical Analysis Division for the Federal Maritime Administration, the 
Operations Research Section developed a mathematical model to assist 
in the location and spacing of such centers, and to estimate some of the 

57 



potential benefits. The model was implemented in a computer pro- 
gram, and exercised in a number of scenarios employing available 
empirical data. 

Precision Measurements for Mapping — NBS is assisting the U.S.A. 
Topographic Command in improving the application of precise micro- 
densitometry and photographic image-structure evaluation in the pro- 
duction of maps. Starting with aerial photographs, cartographers 
employ several intermediate photographic and photomechanical stages 
in the preparation of the plates used to print maps. The assistance pro- 
gram involves training, consulting, preparation of physical standards 
of measurement, and assistance in perfecting measuring techniques. 
The improved ability to measure and quantitatively specify the per- 
tinent image-structure characteristics of the materials at each stage 
should improve quality and effect economies. 

Apollo IX Cameras Calibrated — The cameras used to photograph 
the moon on the Apollo IX mission were calibrated by NBS. Four 
cameras, each utilizing a different spectral region, were mounted in the 
main hatch window. Conventional black-and-white film, infrared film, 
and false-color film were used. The cameras were tested with films 
identical to those used on the flight. NBS measured the lens character- 




Cameras used by Apollo 9 astronauts to photograph the moon were calibrated 
at NBS. 



58 



istics including back focal lengths, effective focal lengths, calibrated 
focal lengths for photogranimetric use, radial and tangential distor- 
tion, resolving-power throughout the field, T-stop settings, lens-trans- 
mittance factor, relative distribution of illumination, and lens-modula- 
tion transfer function. In addition, the shutter speed, shutter efficiency, 
and the wedge angles of the spectral filters were measured. Measure- 
ments were made with and without filters in place and the lenses were 
evaluated by photographic, photoelectric, and visual methods. The 
cameras provided photographs for use in detailed mapping of the 
surface of the moon. 

Electroluminescent Formation Lights — Studies regarding the fea- 
sibility of installing strip-type electroluminescent (EL) formation 
lights on high-performance (mach 2) aircraft have been completed. 
Tests indicate that the EL lamps possess vibrational characteristics 
superior to those of their incandescent-lamp counterparts, while their 
linear geometry conveys better aircraft orientation to formation 
wingmen. These studies have resulted in the specification of EL-type 
formation lights for new aircraft (F-14 and F-15) while preparations 
are underway for retrofitting existing aircraft such as the F-4. 

Field Tests of Fog Detectors — The distance one can see signal lights 
is an important factor in the safety of operation and landing of air- 
craft and in the navigation of ships. As part of the photometry pro- 
gram sponsored by the Department of the Navy, Federal Aviation 
Agency, Air Force, and Coast Guard, the Visual Landing Aids Labo- 
ratory of the Photometry Section, Heterology Division, has completed 
field testing of several types of back-scatter fog detectors at Areata 
Airport, Areata, California — reputedly the foggiest airport in the 
United States. The tests included operational suitability, reliability, 
and correlation of fog-density measurements (obtained by the fog de- 
tectors) with direct measurements of atmospheric transmittance. 

Recommendations on Archival Microfilm — Following several years 
of research on the causes and prevention of blemishes on microfilm, 
the results of a large-scale inspection of government microfilms were 
published, and final recommendations for the prevention of such 
blemishes were presented to the National Microfilm Association and 
the Archivist of the United States. Although there had been practically 
no loss of information, the potential threat to archival records was 
considered serious. The blemishes studied take several forms but are 
most often reddish spots about 0.1 mm in diameter. The blemishes 
were caused by minute amounts of gases generated during long-term 
degradation of the cardboard cartons in which the films were stored. 
Recommendations covered raw film, exposing and processing condi- 
tions, storage conditions, and inspection. For archival purposes, the 
importance of specifying storage and handling conditions as well as 
the characteristics of the films was emphasized. 



375-572—70- 



59 



Physical Properties of Glass-Fiber-Reinforced Plastic Rods — 
Studies were undertaken for the U.S. Coast Guard to develop and 
evaluate test methods for obtaining mechanical and electrical property 
data on glass-fiber- reinforced polymer rods. These rods are used for 
insulator guy systems needed for communications and navigational 
aids towers. The properties studied were tensile strength, creep 
strength, fatigue resistance, effect of ultraviolet radiation, water 
absorption, dielectric strength, and high-voltage flashover resistance. 
From the results of these investigations, a prototype insulator guy was 
specified which will be useful as a laboratory reference for evaluating 
improvements or variations in future insulator guy systems for Loran 
C towers and similar applications. 

Hearing Aids Circular Revised — NBS Circular 534, "Hearing Aids 1 ' 
(1953) has been completely revised and brought up to date. This pub- 
lication is directed toward the consumer and discusses sound and 
hearing, and the general properties, selection, and care of hearing 
aids. It also lists the principal hearing centers in the U.S., at which 
assistance to prospective users of hearing aids is available. 

Radio Standards Information Center — A Radio Standards and 
Measurement Information Center was established to assist the NBS 
technical staff and provide scientists and engineers with information 
on the use of RF standards and calibrations provided by NBS. The 
Center will also provide information on the development, use, and 
evaluation of accurate measurement systems. Outputs include spe- 
cialized bibliographies, survey articles, state-of-the-art reviews, and 
assistance in answering technical questions to the electronics industry, 
universities, private research agencies and standards laboratories, and 
other Government agencies working in the electromagnetic frequency 
range from 30 kHz through the millimeter wave region. Specific sub- 
jects include attenuation, power, noise, field strength, voltage, current, 
impedance, dielectric constant, pulse quantities, horn gain, and antenna 
patterns. 

Radiation Protection Suit — An electromagnetic radiation protection 
garment was evaluated for use at frequencies below 100 MHz. This 
garment was designed to protect personnel who are exposed to high- 
level electromagnetic fields. Measurement techniques were developed to 
evaluate the shielding effectiveness of the suit in the presence of both 
high- and low-level fields. The low-level measurement results were 
encouraging, but high-level tests, using specially developed probes 
for measuring high-level E and H fields (approximately 100 mW/ 
cm 2 ), showed that the suit suffered from arcing and other nonlinear 
effects and hence was unsafe for human use. 

Biomedical Electronic Metrology — Work in biomedical electronic 
metrology has been initiated on a program basis. An extensive study 
was made of measurement needs, which led to the identification of 

60 



appropriate tasks and level of effort. Current work includes design 
of environmental test chambers for studying radiation effects upon 
animals and development of methods for measuring and calibrating 
radiation intensity from ultrasonic diagnostic and therapeutic instru- 
ments. Also, with the support of the HEW Bureau of Radiological 
Health, development was initiated on a new near-zone energy- density 
measurement device for determining the level of stray radiation from 
microwave ovens. 

Apollo 11 Lunar Range Experiment — NBS has cooperated with 
scientists from the University of Maryland, Goddard Space Flight 
Center, Princeton University, Wesley an University, and other institu- 
tions in preparing the optical retro-reflector array that was carried to 
the moon on Apollo 11. The round-trip light travel time from the 
earth to the reflectors and back will be measured using short laser 
pulses. The accuracy of resulting distance measurements is expected 
to be 15 cm or better. One application of the range data will be to deter- 
mine the lunar orbit, librations, and radius to much higher accuracy 
than they are now known. Improved information will also* be obtained 
on the wobble of the earth about its rotation axis, the rotation of the 
earth, and the difference in longitude between widely separated observ- 
ing stations. Such geophysical information should help in under- 
standing the interaction between the core and the mantle of the earth, 
and should provide a direct test of whether the large-scale crustal 
movements predicted by recent theories of ocean-floor spreading and 
continental drift are taking place at present. 

The Cryogenic Data Center — The NBS Cryogenic Data Center has 
a data bank of over 30,000 carefully indexed references to the proper- 
ties of materials at low temperatures. During the past year the Center's 
professional staff noted over 8,300 articles of interest to the field of 
cryogenics in its review of an estimated 340,000 titles, abstracts, or 
full copy of the published and report literature. The articles noted were 
listed in the 52 issues of the "Current Awareness Service" that is now 
sent to 585 paid subscribers. The "Current Awareness Service" com- 
pleted its fifth year of publication in April 1969, and "Superconducting 
Devices" (a quarterly survey prepared in cooperation with Stanford 
Research Institute and the Office of Naval Research) completed its first 
year of publication. There are now 115 paid subscriptions. All pertinent 
documents were entered into the automated information storage and 
retrieval system which is now in machine-readable form and machine 
searchable. A new method of segregating the references stored on mag- 
netic tape was developed. It enabled the initiation of a Selective Dis- 
semination of Information (SDI) program which identifies new 
publications in a particular field of interest. 

Characteristics of Slush Hydrogen — In cooperation with NASA, 
flow characteristics of liquid-solid mixtures of hydrogen (slush hydro- 

61 



>''if--i^ 






:lar{; f l,#f 



S-;«y 







A magnified view of slush hydrogen being pumped through a 1-em orifice. Slush 
hydrogen offers distinct advantages over liquid hydrogen as a rocket propellant. 



gen) in transfer lines have been measured. Losses through a restric- 
tion were also determined with slush and found to be essentially the 
same as with liquid hydrogen. A system was constructed in which the 
solid content of slush could be increased by drawing off liquid and re- 
taining solids with a screen. Using this technique, solid contents greater 
than 50 percent were attained in a dewar of freshly-made slush, while 
solid contents in excess of 60 percent can be realized by aging the 
mixture. Evaluation of stirring devices was made in the system to 
determine criteria for mixing the high-solid-content slush to a homoge- 
neous, flowable mixture. Production of gelled slush hydrogen was also 
accomplished and an analytical expression was derived relating the 
quantity of gellant required to gel slush hydrogen to the quantity 
required to gel liquid hydrogen. Information on the characteristics 
and behavior of slush hydrogen is being sought for studies of appli- 
cations to future space missions, and for the design of ground handling 
equipment. 

Conferences and Symposia 

Precision and Accuracy in Measurement and Calibration — A West 
Coast location was selected for a 3-day seminar on statistical tech- 
niques that had been presented four times in Washington. The Bureau 
reported experience in the development and use of statistical experi- 



62 



ment designs especially tailored to the needs of calibration laboratories 
for making economical intercomparisons among sets of standards. 
Presentations by NBS statisticians were complemented by reports 
from Bureau calibration laboratories that are implementing the new 
computer-aided methods for data analysis, preparation of calibration 
reports, and surveillance of the measurement ("production") process. 
The seminar was held at the West Coast University in Orange, Cali- 
fornia, and was sponsored by the National Conference of Standards 
Laboratories. Participants were 37 metrologists from industrial and 
government laboratories. 

Photometry Seminar — Thirty-five registrants from photometric lab- 
oratories of private industry and government agencies participated in 
a four-day seminar on photometry given by the Photometry Section 
of the Metrology Division May 12 through 16, 1969. The seminar 
included lectures given by staff members on photometric quantities and 
terminology, photometry and the eye, photometric standards and 
methods, and projection photometry. The lectures were supplemented 
by laboratory visits and demonstrations and with individual confer- 
ences with staff members. A similar seminar was held earlier for 14 
representatives of Navy standardizing laboratories. 

Symposium on Thermal Expansion of Solids — Jointly sponsored by 
the Westinghouse Astronuelear Laboratory and NBS, this first sym- 
posium emphasized the complete spectrum of techniques used in meas- 
uring the thermal expansion property. The program consisted of 12 
invited and 24 contributed papers, including a historical review of the 
theory of thermal expansion, a description of recent measurements at 
low temperatures, a review of x-ray and neutron diffraction methods, 
and a description of measurements at high temperatures with neutron 
diffraction. More than 100 scientists attended the three-day sym- 
posium, September 18-20, 1968. 

Length, Angle, and Geometry Measurement Seminar — Thirty-two 
dimensional metrologists from industry and government standards 
laboratories and from the George Washington University Graduate 
School participated in a 5-day seminar. Lectures by KBS staff, labora- 
tory sessions, and discussion periods covered: gage blocks; optical 
and mechanical measurement of length, angle, diameter, and flatness; 
gear metrology; and statistical programs for determination of th^ 
accuracy of measurement. 

Fundamentals for Gas-Laser Length Measurement Seminar — 
Metrologists, physicists, and mechanical engineers from university, in- 
dustry and Government participated in a 2-day seminar. Forty-one 
persons attended lectures by NBS staff covering fundamental inter - 
ferometry, gas lasers, holography, NBS laser instrumentation, and 
practical pointers on use of lasers. 

Symposium on High Pressure — An international symposium on "Ac- 

63 



curate Characterization of the High Pressure Environment" was held 
at the NBS October 14-18, 1968 and attended by 140 participants from 
the United States and abroad. Thirty-eight papers were presented, and 
four panel sessions were held covering current research at high pres- 
sures in static systems and in shock wave experiments. In panel sessions, 
five fixed points below 100,000 bars were proposed, and values for these 
points recommended. The equation of state of sodium chloride was 
recommended as a standard for the x-ray determination of pressure. 
The measurement of temperature in high-pressure apparatus and the 
measurements of phase transformations as a function of temperature 
and pressure using static and dynamic techniques were presented. 
Dynamic methods included studies of phase transformations ranging 
from 20,000 bars up to several million bars. Recent developments in 
static high pressure were also presented. 

Short Courses in Noise and Power Measurements — By special re- 
quest, two brief measurement courses were presented to specially 
selected U.S. Air Force personnel. One 4-day course covering RF power 
measurements was presented in February 1969, and a 5-day course 
covering both high-frequency and microwave measurements in noise 
was presented in April 1969. Both courses were designed to satisfy the 
specific needs of the Air Force and included discussions of NBS 
measurement techniques as well as anticipated Air Force measurement 
problems. 

Seminars on Frequency and Time Stability — One hundred and 
twenty-two registrants from private industry and government agen- 
cies attended two seminars on Frequency and Time Stability given by 
NBS on February 18-20 and June 3-6, 1969. Four foreign countries 
were represented. The seminars developed a language that allows clear 
characterization of the instabilities in frequency standards. Measure- 
ment methods were described for obtaining data on the stability of 
precision signal sources such as cesium beams, hydrogen masers, 
rubidium gas cells, and quartz crystal oscillators. Flicker noise and 
other commonly encountered noises were discussed. 

NATIONAL STANDARD REFERENCE DATA SYSTEM 

The production of scientific information has undergone explosive 
growth during the past decade. Furthermore, the development of 
sophisticated instruments has meant that a greater part of this informa- 
tion is in the form of quantitative numerical data. These numerical 
data are essential to the advancement of scientific understanding, the 
planning of new research, and the utilization of research results in 
industry. However, the great mass of data now being produced has 
led to a serious problem in locating the data needed for a particular 
purpose and ensuring that it is the best available. The National Stand- 

64 



ard Reference Data System aims to solve this problem by collecting 
data from the world scientific literature, subjecting it to critical evalua- 
tion by experts, and condensing it into an accessible and easily usable 
form. 

The National Standard Reference Data System (NSRDS) was es- 
tablished in 1963 under a directive from the Federal Council for Sci- 
ence and Technology and the President's Office of Science and 
Technology. The primary functions of NSRDS are: (1) to sponsor 
projects for the compilation and critical evaluation of numerical data 
in technical areas where the need for such data is clear; (2) to coordi- 
nate data compilation activities throughout the Government; (3) to 
establish standards of quality for products of the system; and (4) to 
develop techniques for handling and disseminating scientific data. The 
scope of the program is currently limited to well-defined properties of 
well-characterized physical systems. These boundaries are not perfectly 
sharp ; however, the emphasis is on intrinsic properties which can be 
measured in a reproducible way and which are clearly defined in terms 
of universally accepted physical theory. 

The core of NSRDS is made up of a group of data centers, each of 
which is responsible for a clearly defined technical area. There are 
currently about 25 of these centers. Roughly half are located in the 
technical divisions of the National Bureau of Standards, and the re- 
mainder are supported on a contract basis in universities, Government 
laboratories and industrial laboratories in all parts of the country. 
Each data center is responsible for the various phases of compilation 
of data within its technical scope. These consist of (1) locating the 
pertinent publications in the scientific literature; (2) indexing and 
abstracting the publications; (3) extracting and compiling the nu- 
merical data; and (4) subjecting the data to a critical evaluation in 
order to obtain a set of recommended values. The last phase is the most 
critical one and requires the intellectual input from experts who are 
experienced in the particular field. Every effort is made to utilize the 
services of outstanding research leaders for this critical evaluation 
phase. 

The tangible products of NSRDS consist of tables of critically 
evaluated data, accompanied by a detailed discussion of the criteria for 
evaluation and a critique of the measurement techniques by which the 
raw data were obtained. Ideally, such a publication provides the best 
set of numbers for a scientist or engineer to use. In addition, it points 
out gaps in our existing knowledge and deficiencies in the measure- 
ment techniques, and thus helps to stimulate and guide future re- 
search. This feedback mechanism, by which the level of measurement 
and interpretation of scientific data can be upgraded, is regarded as 
one of the most important functions of NSRDS. It has, of course, 
always been one of the principal goals of the National Bureau of 
Standards. 

65 



The activities of NSRDS were given a specific congressional man- 
date through legislation enacted by the 90th Congress in July, 1968. 
The Standard Reference Data Act (PL 90-396) contains the follow- 
in or provisions: (1) a declaration that it is the policy of the Congress 
to make critically evaluated reference data readily available to scien- 
tists, engineers, and the general public ; (2) a directive to the Secretary 
of Commerce to provide or arrange for the collection, compilation, 
critical evaluation, publication, and dissemination of standard ref- 
erence data; (3) a directive to the Secretary of Commerce to prescribe 
standard criteria and procedures for the preparation and publication 
of standard reference data, as may be necessary; (4) authority for 
the Secretary, or a person or agency designated by him, to sell standard 
reference data and to allow the proceeds to be used by the Bureau; 
and (5) authority for the Secretary to obtain copyright, on behalf of 
the United States as author or proprietor, for standard reference data 
prepared or made available under the Act. This Act provides the 
authority for more varied channels of distribution of standard ref- 
erence data. Plans are now being developed to utilize this authority. 

Current Activities 

The activities of NSRDS are classified under eight program areas ; 
six of these represent technical areas in which data compilation proj- 
ects are active ; the remaining two cover more general functions car- 
ried out in the Office of Standard Reference Data. A summary of 
recent accomplishments and current activities in each program area 
is given below. 

Nuclear Data 

An NAS-NRC advisory panel meeting on nuclear data was held 
in November, 1968. The general conclusion of the meeting was that 
OSRD should work toward sharing the responsibility for financial 
support in the area of nuclear data, which previously has been almost 
entirely in the hands of the Atomic Energy Commission. The first 
step to implement this recommendation was taken in an agreement 
between OSRD and the AEC to provide joint support for the Berkeley 
Particle Data Center, which for several years has been compiling and 
publishing elementary particle data. Proposals for other projects on 
nuclear data are being studied, and it is hoped that some of these can 
be funded during the next year. 

The Proceedings of the Neutron Cross Section and Teclmology 
Conference were published in two volumes with D. T. Goldman, Editor, 
as NBS Special Publication #209 (1968). The Program Manager 
also chaired a meeting of an ISO Working Group, in May, which was 
concerned with additions to the International Nuclear Energy Glossary 
of Terms. 

66 



Atomic and Molecular Data 

This program has emphasized the production of reference data com- 
pilations in categories designated as highly important to the technical 
community by its advisory panels. Considerable emphasis during the 
past year was given to the publication of infrared spectral data based 
on the criteria established by the Board of Managers of the Coblentz 
Society. The first 1,000 research quality spectra have been issued and 
plans are underway for the preparation and issuance of the second 
group of 1,000 spectra. The success of this project has encouraged the 
initiation of similar activities in the fields of Nuclear Magnetic Reson- 
ance, Raman Spectroscopy, and Mass Spectrometry. An advisory 
group meeting to examine criteria for the publication of microwave 
spectra is also being planned. In addition to these activities, an ad hoc 
advisory panel met on May 27, 1969, to provide guidance for the com- 
pilation of interatomic distances in gas-phase molecules. 

The following reports have been published : 

1. "Theory of the Ionization of Atoms by Electron Impact," by 
M. R. H. Rudge, reprinted from Reviews of Modern Physics, 
Vol. 40, No. 3, July 1968. 

2. NSRDS-NBS-26, "Ionization Potentials, Appearance Poten- 
tials, and Heats of Formation of Gaseous Positive Ions," by J. L. 
Franklin and J. G. Dillard of Rice University, H. M. Rosenstock, 
J. T. Terron, K. Draxl of NBS, and F. H. Field of Esso Research 
and Engineering Company, 1969. 

3. ORNL-AMPIC-11 and 12, "Bibliography of Atomic and Molec- 
ular Processes for January-December 1968," compiled by Atomic 
and Molecular Processes Information Center, Oak Ridge Na- 
tional Laboratory, under the direction of Dr. C. F. Barnett, 1969. 

4. NSRDS-NBS-23, "Partial Grotrian Diagrams of Astrophysical 
Interest," by Dr. Charlotte E. Moore and Paul W. Merrill, 1968. 

5. Special Publication 306-1, 2, and 3, "Bibliography on the Anal- 
yses of Optical Atomic Spectra, Sections 1, 2, and 3," by 
Dr. Charlotte E. Moore. 

6. NBS Monograph 70, Volumes III, IV, and V, "Microwave Spec- 
tral Tables," by Paul F. Wacker, Marian S. Cord, Donald G. 
Burkharcl, Jean D. Petersen, and Raymond F. Kukol, Matthew 
S. Lojko and Rudolph H. Haas, 1968, 1969. 

7. NBS Technical Note 474, "Critically Evaluated Transition 
Probabilities for Ba i and n," by B. M. Miles and W. L. Wiese, 
1969. 

Solid State Data 

The activities in the solid state program are reflected largely through 
the continuing efforts of the data centers established in this area. The 
assembly of bibliography and the preparation of compilations on 

67 



crystal data, alloy data, superconductor properties, and diffusion data 
are in progress. Two of the contributing efforts are being carried out 
in India. They are "Phase Transformation in Solids," under the direc- 
tion of C. N. R. Rao, and "Crystal Defects in Alakli Halides," under 
the direction of S. C. Jain. 

The following reports have been issued : 

1. NBS Technical Note 464, "The NBS Alloy Data Center: Func- 
tion, Bibliographic System, Related Data Centers, and Reference 
Books," by Gesina C. Carter with L. H. Bennett, J. R. Cuthill, 
and D. J. Kalian, 1968. 

2. NBS Technical Note 482, "Superconductive Materials and Some 
of Their Properties," by B. W. Roberts, General Electric Re- 
search and Development Center, 1969. 

Thermodynamic and Transport Properties 

During the past year, projects initiated earlier were carried on under 
Office of Standard Reference Data sponsorship in the following areas : 
Chemical Thermodynamic Data on Inorganic Compounds 
Thermodynamic Data on Organic Compounds 
Properties of Molten Salts 

Thermodynamic Properties of Polar Gases: Ammonia 
Low Temperature Specific Heats 

Thermodynamic Properties of Liquid Metals and Liquid Oxides 
Systems at High Pressure 
Vapor-Liquid Equilibrium in Binary Mixtures of Non-Electrolytes 

at Low Pressures 
Binary Metal and Metalloid Constitution Diagrams 
Thermal Conductivity of Selected Materials, Including the Elements 
Viscosity and Thermal Conductivity of Mixtures in the Gaseous and 

Liquid States 
Transport Properties of Fluids 

Two new projects were initiated on the evaluation of data near the 
critical points of binary liquid mixtures and on the thermodynamic 
properties of nitrogen. The first of these complements a program on 
the liquid-vapor critical region being carried out under other sponsor- 
ship. Together the programs constitute a thoroughgoing evaluation 
of the data in a region which is difficult experimentally but of great 
theoretical and practical interest. The project on nitrogen, in addition 
to its own intrinsic importance, is coordinated with an international 
program under the auspices of the International Union of Pure and 
Applied Chemistry. 

Additional continuing projects under other sponsorship are also 
being carried out in the following fields : 

Properties of Electrolyte Solutions 

Thermodynamic Properties of Metals and Alloys 

68 



Thermodynamic Functions of Cryogenic Fluids 

Thermal Conductivity of Metals and Alloys at Low Temperatures 

The Annual Index of Worldwide Published Thermochemical 
Studies continues to be published yearly under the auspices of the 
International Union of Pure and Applied Chemistry, with substantial 
support from the Office of Standard Reference Data. 

Several projects have resulted in major published reports during 
the year. These reports are : 

Molten Salts, Vol. 1, Electrical Conductance, Density, and Viscosity 
Data, G. Janz, F. W. Dampier, G. R. Lakshminarayanan, P. K. 
Lorenz, and R. P. T. Tomkins, NSRDS-NBS-15, 1968 

Theoretical Mean Activity Coefficients of Strong Electrolytes in 
Aqueous Solutions from to 100 °C, Walter J. Hamer, NSRDS- 
NBS-24, 1968. 

Thermodynamic Properties of Argon From the Triple Point to 300 
K at Pressures to 1000 Atmospheres, A. L. Gosman, R. D. Mc- 
Carty, and J. G. Hust, NSRDS-NBS-27, 1969. 

Selected Values of Chemical Thermodynamic Properties, Tables for 
Elements 35 Through 53 in the Standard Order of Arrangement, 
D. D. Wagman, W. H. Evans, V. B. Parker, I. Halow, S. M. 
Bailey, and R. H. Schumm, NBS Technical Note 270-1, 1969. 

Ionization Potentials, Appearance Potentials, and Heats of Forma- 
tion of Gaseous Positive Ions, J. L. Franklin, J. G. Dillarcl, H. M. 
Rosenstock, J. T. Herron, K. Draxl, and F. H. Field, NSRDS- 
KBS-26, 1969. 

The last named was sponsored under the program in Atomic and 
Molecular Properties but is of importance in the area of Thermo- 
dynamic and Transport Properties as well. Reports have been received 
in several other areas which should result in publications in the coming 
year. 

Colloid and Surface Properties 

There are six current projects in the field of colloid and surface prop- 
erties. These cover the following fields : 

Surface Tensions of Molten Salts 

Critical Micelle Concentrations of Aqueous Surfactant Systems 

Surface Tensions of Substances Liquid in the Vicinity of Room 

Temperature and Below 
Light Scattering by Liquids 
Electrical Properties of Interfaces 
Physical Data Pertaining to Phase Transition Kinetics 
A report on the surface tensions of molten salts is in press and two 
others are in the final stages of preparation. 

69 



Chemical Kinetics 

A meeting of the Chemical Kinetics Advisory Group under the 
chairmanship of Dr. S. W. Benson was held on May 19, 1969. This 
group affirmed the view that the principal aims of the program should 
be directed toward compilations of chemical kinetic data and mono- 
graphs for reactions in the gas phase. They also recommended the 
preparation of bibliographies for the assistance of those authors carry- 
ing out critical evaluations on subjects such as solution kinetics. The 
importance of varied approaches embracing data sheets, short reviews, 
and complete critical evaluations was endorsed. 

The program has been responsive to this advice. The two data 
centers have prepared bibliographies for use by authors preparing 
critical evaluations. Data sheets covering the radiation chemical 
behavior of six compounds are in preparation. A compendium of rate 
constants embracing approximately 1,500 reactions has been compiled. 
The establishment of new data centers is under consideration. 

The following reports have been issued : 

1. NSRDS-NBS-20, "Gas Phase Reaction Kinetics of Neutral 
Oxygen Species," by Harold S. Johnston, University of 
California, 1968. 

2. NBS Technical Note 484, "A Review of Rate Constants of 
Selected Reactions of Interest in Re-Entry Flow Fields in the 
Atmosphere," by M. H. Bortner, General Electric Company, 
1969. 

3. NBS Report 9884, "A Compendium of Evaluated and Estimated 
Rate Coefficients," by David Garvin, 1968. 

4. "The Biradical Mechanism in Small-Ring Compound Reactions," 
by H. E. O'Neal and S. W. Benson, reprinted from the Journal 
of Physical Chemistry, 72, 1866 (1968). 

Data Systems Design 

The major efforts of the Data Systems Design Group have been 
divided among two coequal activities : 

(a) design of and programming support for computer-assisted 
typesetting and composition of data tables and associated tex- 
tual and bibliographic material, and 

(b) development of a comprehensive package of general-purpose 
programs for data file manipulation. 

, Work has been completed on a series of general-purpose computer 
programs for automatic typesetting of computer-generated text and 
tables. One of these (TYPSET) handles program listings and for- 
matted computer printout. Another called KWIND is specialized to 
typesetting KWIC (keyword in context) indexes. Both programs 
have provisions for converting the normal upper-case computer out- 
put to a more readable format with upper- and lower-case characters, 
and even Greek characters where appropriate. 

70 



In the area of data file manipulation a series of programs have been 
written to reformat and edit data files in three categories : 

( a ) fixed-field files of fixed-length records, 

(b) free-field files of structured but variable-length records, and 

(c) free-field unstructed files of variable-length records which have 
been suitably flagged. 

For files which satisfy the above characteristics the programs per- 
mit exceptionally easy file manipulation. 

The programs have been documented in a series of Technical Notes 
issued through the Superintendent of Documents. 

A distribution system for general-purpose computer programs on 
magnetic tape has been started as a pilot program for a larger effort 
on NSRDS data tapes. The machinery for distribution of magnetic 
tapes via the Clearinghouse for Federal Scientific and Technical In- 
formation is proving quite successful, judging from the reception by 
the technical press of the release of the first magnetic tape in the series. 

Information Services 

Despite the limited financial resources of the Office of Standard 
Reference Data, which have imposed severe restrictions on Informa- 
tion Services, this operation is continuing to progress and to make 
effective contributions to the NSRDS program. Some of the contribu- 
tions are : 

Data File — The Data File has established a very comprehensive 
collection of worldwide compilations of data in the physical sciences. 
Its holdings of reference data compilations are as extensive as will be 
found anywhere in the world. An annotated accession list of the hold- 
ings is in preparation. 

Compilation and Editorial Services — This unit is responsible for 
the monthly NSRDS News. This newsletter has a worldwide circula- 
tion of over 4000 subscribers. This unit also acts as the editorial inter- 
mediary between the Office of Standard Reference Data, associated 
data centers and projects producing data compilations on the one hand 
and the government publication mechanism on the other. In the pres- 
ent reporting period, 20 publications have been produced and 17 are 
in process. 

Inquiry Services — This unit provides coordinated replies to inquiries 
received by the Office of Standard Reference Data from the Data 
File, from the Compilation and Editorial unit of the Office, and from 
other sources in the NBS and NSRDS associated centers. If the query 
is within the capability and scope of the program, a reply is forwarded. 
Sometimes inquiries are referred elsewhere or reference sources fur- 
nished, or data compilations or other publications are provided. In 
the present reporting period, 558 inquiries were received, compared to 
400 in the previous year. 

71 



Analysis and User Relations — In order to develop an effective in- 
formation system to provide broad coverage of properties data in the 
physical sciences with a flexibility capable of meeting the needs of a 
large variety of specialists, this unit has been examining the users, 
actual and potential, of standard reference data. Toward this end, it 
conducted two very preliminary studies. The first queried by mail 212 
persons who received NSKDS publications as to the use and usefulness 
of the publications received. Ninety-eight returns were received 
(47%). Of these, 86 indicated they found the NSKDS publications 
useful ; 4 indicated they did not find them useful ; one did not reply 
to that question; and 7 did not remember the publication. 

The second effort was a pilot survey in the form of an interview/ 
questionnaire aimed at providing information on technical reference 
data use patterns of NBS scientists. This pilot study revealed that 42, 
or 84 percent, of a representative sample of 50 NBS scientists use physi- 
cal properties data. These scientists, on the average, spend approxi- 
mately one hour of their working day in seeking or discussing their 
data requirements. One of the results of this pilot study is a revised 
interview/questionnaire suitable for survey of similar information 
by other organizations. 



72 



INSTITUTE FOR MATERIALS RESEARCH 

Emphasis in the Institute for Materials Research (IMR) is on 
measurement methodology for well-characterized materials. This em- 
phasis supports the unique mission to develop standards of measure- 
ment for the commercial, industrial, and educational communities of 
the Nation and to provide research and consulting services to other 
Government agencies. About 25 percent of IMR's work is for other 
Government agencies. 

Work falls into the following broad areas : 

1. Preparation and characterization of materials 

2. Standard Reference Materials 

3. Data on the properties of materials 

4. Technical assistance to others. 

PREPARATION AND CHARACTERIZATION 
OF MATERIALS 

This area includes such activities as the synthesis of new materials, 
purification of materials, crystal growth, and the analysis of materials 
with respect to chemical composition and structure. Outputs of these 
activities are sample materials to be used for specific research purposes, 
and the development of new techniques and procedures for preparing 
or characterizing materials. 

Preparation 
Synthesis 

Synthesis of Organoboron Compounds — A number of new or- 
ganoboron compounds have been synthesized for the first time. Two 
of these, ethynyldichloro- and ethynyldifluoroborane, are the first re- 
ported members of the hitherto unknown family of organoboron 
halides of the acetylenic series. The syntheses were carried out using 
both photochemical and conventional synthetic techniques. The com- 
pounds appear to be significantly more stable than most boron- 
substituted acetylenes. Since they are thus amenable to detailed physi- 
cal investigation, they are of considerable interest for detailed studies 
of structure and bonding in technologically important organoboron 

73 



derivatives. Preliminary microwave spectroscopic studies have been 
carried out in cooperation with members of the Institute for Basic 
Standards. Some novel organo-substituted compounds containing 
boron-boron bonds have also been prepared and are of particular 
interest as new derivatives containing preformed aggregates of boron 
atoms. The new compounds are being investigated both from the 
viewpoint of their fundamental chemistry and as possible precursors 
to useful boron-containing materials such as the borides. 

Organometallic Complexes of Biological Interest — Interactions be- 
tween transition metal ions in binuclear complexes have been observed 
in a large number of compounds. Research in this area has been ex- 
tended, in a cooperative study with chemists at the State University of 
New York at Plattsburgh, to include complexes of biologically sig- 
nificant ligands such as the purine bases. Dimeric adenine complexes 
of copper (II) have been synthesized in both neutral and anionic forms, 
and the magnetic behavior of such complexes has been studied by 
electron paramagnetic resonance spectroscopy. These compounds are 
the first reported examples of purine-base complexes with unusual 
magnetic properties attributable to exchange-coupled metal-ion pairs. 
The complexes are of interest as model compounds for a number of 
biological systems, particularly in view of recent suggestions that the 
occurrence of metal ion pairs may be significant in biological processes 
involving enzymes and proteins with trace metal ions. 

Reactive Intermediates in Chemical Synthesis — In the past several 
years increasing recognition of the importance of synthetic chemical 
processes derived from highly energetic conditions has resulted in an 
array of novel and useful chemical structures. To a large extent these 
advances have derived from the development of the characterization 
and descriptive chemistry of reactive intermediates — small molecules 
or molecular fragments produced thermally, by photo excitation, or in 
plasmas or flames — which determine the chemical pathways available 
outside the energy zone. 

In previous studies, complex product mixtures resulting from inter- 
actions of low-density fluoride plasmas with ceramic or organic poly- 
mer materials were rationalized in terms of a few key reactive 
intermediates. Such an approach has been extended to examination of 
materials such as organometallics and their halides upon subjection 
to comparatively lower energy irradiation with visible and ultraviolet 
light. Primary and secondary reactions which occur at rates sufficiently 
different to permit identification by electron spin resonance (ESR) or 
mass spectrometry have been demonstrated. Solid solutions of methyl- 
trichlorosilane and trichlorosilane show non-additive behavior at liquid 
nitrogen temperatures, where the methyl free radicals associated with 
photo-cleavage of methyltrichlorosilane by itself disappear in the pres- 
ence of trichlorosilane to form a new, complex radical product. The 

74 



potential of such "reagent" intermediates for specific free radical 
syntheses is further illustrated by the photolysis of phosphorus tri- 
chloride at liquid nitrogen temperatures. The primary photo-cleavage 
reaction produces a novel radical, PCL, along with mobile, reactive 
chlorine atoms. The latter produce secondary reactions with unreacted 
PC1 3 molecules to generate still another new radical, PC1 4 . Dilution 
experiments with the inert gas Xe indicate the secondary process can 
be inhibited in the solid PC1 3 matrix. 

15 N -Labeled Amino Sugars — Naturally occurring sugars that possess 
a chemical structure in which one or more oxygen atoms is replaced 
by a nitrogen atom are often found as components of substances, such 
as antibiotics, which have important biological functions. IMR scien- 
tists have now synthesized the first amino sugars having a 15 N-content 
greater than 99 percent to study the nuclear magnetic properties of 
the isotope-labeled compounds and the potential of 15 N magnetic res- 
onance parameters for structural analysis. 

Periodic Acid, a Novel Oxidant for Organic Compounds — Controlled 
oxidation of organic compounds is an important step in the synthesis 
of pharmaceuticals and other substances of biomedical significance. 
Periodic acid, a reagent well known for its ability to cleave 1,2-diols, 
has now been found also to be a useful oxidant of polycyclic, aromatic 
hydrocarbons. A unique, two-fold character of response to periodic acid 
by such hydrocarbons has been observed : production of ( 1 ) coupling- 
reaction products through a radical intermediate, or (2) quinones by a 
two-equivalent oxidation mechanism that does not involve a radical 
intermediate. A most interesting example is the oxidation of the hydro- 
carbon azulene with periodic acid, which gives a polymerical product 
that is highly paramagnetic and retains this free-radical property for 
some time at 485 °C. 

Crystallization and Morphology of 66 -Nylon — Current investiga- 
tions are primarily aimed at determining the nature of the crystalliza- 
tion habit exhibited by 66-nylon when it is crystallized from dilute as 
well as concentrated solutions of the polymer in glycerol. The objective 
of this study is, among other things, the elucidation of the manner in 
which the chain molecules of this polyamide fold during crystallization. 
The polymer has been observed to crystallize in a variety of forms de- 
pending on the condition of crystallization. Among the habits observed 
on crystallizing from dilute solutions are simple parallelepiped lamel- 
lae as well as multi-layered lamellae crystals whose constituent chain- 
folded layers are apparently twisted. Concentrated solutions have been 
observed to yield on cooling complex petal-shaped aggregates as well 
as negatively birefringement spherulites. The relationship between 
these and other forms of crystallization exhibited by 66-nylon is being- 
studied. 



375-572—70- 



75 





ill 



m 



■■■■■I 



1..'"^ ..... 






mm 
m 






ilk 



■h 






hm 




66-Nylon is being studied to determine the manner in which the chain molecules 
fold during crystallization. Shown here is a scanning electron micrograph of 
(X520) spherulites and other aggregates (top left) of 66-Nylon grown from a 
concentrated solution of the polymer in glycerol. 



Polymerization at High Pressure — High pressures (10-20 kbars) 
have been utilized to produce new fluorinated copolymers of 
tetrafluoroethylene with the olefins 3,3,3-trifluoropropene ; 3,3,3,2- 
tetrafluoropropene ; 2-trifluoromethyl-3,3,3-trifluoropropene ; and 
3,3,4,4,5,5,5-heptafluoropentene-l. At autogeneous pressures only 
liquids and oils are produced, instead of the strong high molecular 
weight copolymers produced at high pressures. The comonomers all 
have some retardation effect on the polymerization of tetrafluoro- 
ethylene. The objective of the research which is sponsored by AQDP is 
the expansion of our basic comprehension of the molecular and struc- 
tural factors that determine the mechanisms of polymerization, the 
nature of the transition state, and the molecular size. 

The composition of the copolymers produced at various pressures 
from 3,3,4,4,5,5,5-heptafluoropeiitene and tetrafluoroethylene is a 
function of the composition of the monomer charged. The pressure 
does not affect the composition appreciably, although it drastically 
enhances the molecular size. Reactivity ratios found for these sys- 
tems work against incorporation of the tetrafluoroethylene in the 



76 



copolymer. The rate of these copolymerizations becomes much more 
rapid at high (10:1) ratios of tetrafluoroethylene to the other 
monomer. 

Separation of Polymer Molecules by Flow — The basic idea behind 
separation by flow is easily explained. An isolated polymer molecule 
flowing through a thin capillary and undergoing Brownian motion 
will have an average velocity greater than that of the solvent. This 
is because the center of the particle (assumed to be a rigid sphere) 
cannot get any closer to the walls of the capillary than its radius. It 
therefore samples only those solvent velocities away from the walls; 
since the solvent velocity is larger, the farther the distance from 
the wall, larger molecules will have larger average velocities than 
smaller molecules. This "Separation by Flow" mechanism has been 
advanced as the fundamental basis for the phenomenon of Gel Per- 
meation Chromatography. The quantitative understanding of this 
basic phenomenon thus now allows the systematic design of instru- 
ments to separate molecules or particles of different size. 

Chelating Agents as Potential Adhesives for Dental Restorations — 
One of the unsolved problems in restorative dentistry is the lack of 
adhesion between tooth tissues and permanent restorations under 
conditions existing in the oral cavity. Micro-leakage between cavity 
and restoration can result in secondary caries. In the present work, 
supported by the Dental Division of the United States Army Medical 
Kesearch and Development Command, potential adhesive liners that 
may bond to tooth structure and plastic restorative materials have 
been studied. These tailor-made molecules were selected on the basis 
of theoretical considerations taking into account the chemical com- 
position of the tooth surface and the compatibility of these com- 
pounds with cold curing acrylic restoratives. The newly synthesized 
compounds contained groups that react with calcium to form che- 
lates and other groups that could copolymerize with dental resins. 

Dentinal and enamel bovine tooth surfaces were treated with these 
compounds and the adhesion to a cold curing acrylic resin was then 
determined. The teeth were stored up to 30 days at 37 °C in solutions 
of different acidities. The tensile strength of the bond between tooth, 
liner, and restorative material was taken as a measure of the bonding 
efficiency of a compound. Treatment of the dentinal and enamel 
surfaces with most chelating agents produced only insignificant in- 
creases in bond strength or gave results that were not always repro- 
ducible. However, applications of dilute aqueous solutions of many 
heavy metal salts changed the surface of the enamel within a few 
seconds so that the restorative resin adhered even without the use 
of an intermediate liner after storage in water for 24 hours. This 
behavior can be explained by the formation of secondary covalent 
bonds, causing weakening of the bond of the resin's ester group on 

77 



prolonged exposure to water. The results with similarly treated dentin 
surface showed less adhesion, but were promising enough to justify 
continuation of this line of investigation. It is hoped that the use of 
potential adhesives in combination with treatment of the surfaces 
with metal salt will lead to improved bonding at the tooth surface- 
acrylic interphase. 

Electrodeless Electrolysis — Both solid materials and fused salts 
have been electrolyzed without being in contact with any solid con- 
ductor. The current was carried to the materials via glow discharge 
in a gas at a pressure of about 0.1 torr. Under these conditions some 
ceramics became electrically conducting, and dendrites of nickel, 
cobalt, copper, silver, tin, and magnesium were deposited from fused 
salts. The experiments show that metallic electrodes are not essential 
for electrolysis to occur. 

Vapor Growth of AL0 3 Bicrystals — IMR has, with the support of 
the Advanced Research Projects Agency, developed a technique to 
grow aluminum oxide mono- and bicrystals by a vapor transport proc- 
ess. Monocrystals are being grown by this method with the goal of 
higher purity in order to improve the measurements of many physical 
and chemical properties. Bicrystals are being grown in order to meas- 
ure properties of the interface. 

Basically, the process consists of reacting A1C1 3 with oxygen under 
carefully controlled conditions of pressure and temperature with the 
resultant deposition of AL0 3 in single crystal form in a seed. By the 
use of double seed crystals, bicrystals containing symmetrical tilt 
boundaries have been grown in sizes suitable for research specimens. 
The purity of the crystals is quite high, of the order of 40 ppm by 
weight, or less, total cation impurities. 

Morphology of Ice Cylinders — Recent experimental and theoretical 
results have shown that the initial morphology of growing crystals can 
be predicted. Experiments on the growth of single-crystal ice cylinders 
in slightly supercooled water have been carried out. The initially 



W\ 







> 



wr* 






Experiment has confirmed theoretical predictions of the initial morphology of 
growing crystals. Shown here are pertubations on the surface of ice cylinders 
at supercooled temperatures —0.20, —0.09, and —0.08 °C, left to right. 



78 



smooth cylinder develops approximately sinusoidal perturbations 
parallel to the axis of the cylinder. The wavelengths, A, of these 
perturbations have been measured as a function of the bath under- 
cooling, AT. Based on a morphological stability analysis, theory pre- 
dicts that of all possible wavelengths, the wavelength of maximum 
amplification will appear on the growing cylinder. Excellent agree- 
ment has been obtained between the theoretical prediction and the 
experimental results. The sinusoidal perturbations are the precursors 
of dendritic growth. Thus, the initial stages of the development of 
dendrites can be successfully treated by morphological stability theory. 

Melt Growth of Cuprovs Oxide Crystals — As a part of a crystal 
growth project sponsored by the U.S. Atomic Energy Commission, 
large single crystals of Cu 2 have been grown by a float zone process in 
controlled oxygen pressures. Typically, crystals of 1.5 cm diameter 
and up to several centimeters long have been grown, with total cation 
impurities of less than 40 ppm. 

New Technique for Target Current Scanning in Electron-Probe 
Microanalysis — In the electron-probe microanalyzer, a beam of elec- 
trons focused on the surface of a specimen produces x rays, secondary 
electrons, and a current from specimen to ground, known as target 
current. The target current signal, which is affected by the back scat- 
tering of electrons, varies both with composition and topographic 
variations of the specimen surface. 

In IMR laboratories, a concept has been developed for handling 
the target current signal in a way that permits separating and empha- 
sizing the topographic aspects of a specimen independent of composi- 
tion. This may render unnecessary in many cases the installation of 
secondary electron detectors and associated electronics. An amplifier 




Target current scans of titanium boride contaminated with iron. The iron shows 
as the bright phase in the upper image. Upper image : linear target current, 
showing atomic number differences. Middle image : derivative image, showing 
topography. Lower image : combination of both signals. 



79 



has been constructed in which the target current signal and its first 
derivative are amplified and recombined in any desirable proportion. 
Application of this concept in the examination of a titanium boride 
specimen makes evident both the surface topography and the distribu- 
tion of iron impurity. 

Multi-Element Trace Analysis by Isotope-Dilution Spark-Source 
Mass Spectrometry — Highly sensitive methods have been developed 
for trace analysis of high-purity materials using the spark source 
mass spectrometer with isotope dilution techniques. In a typical anal- 
ysis, for example, the determination of trace elements in zinc, a solu- 
tion of the zinc is spiked with isotopically enriched solutions of the 
elements to be determined, the elements are electroplated onto high- 
purity gold wires, and the wires are sparked in the mass spectrometer. 
By measuring the mass spectra and applying appropriate calcula- 
tions, the concentrations of the trace elements in the original zinc 
sample are determined. 

The method permits the simultaneous determination of groups of 
six or more elements and provides determinations at concentrations 
of parts per billion, e.g., 20 ppb tin in zinc. The method was developed 
especially to provide analyses of NBS standard reference materials 
and has been applied to analyses of zinc, platinum, and gold. Further 
work indicates general applicability to the analysis of other materials 
such as steel and glass. 




7 






HB 



«£fi 






IK 



pirn, 



i «wiiffiii 




f 





'■■■■I-. '>4\M'i¥ "' III!** 



iii s? 



■ '™ : 



Cell for electroplating impurity elements from isotopically modified solutions 
onto gold electrodes prior to mass spectrometry trace analysis. 



80 



Improved Trace-Element Analysis — A new approach has been de- 
veloped that offers at least a hundred- fold improvement in the 
selectivity and sensitivity of many existing spectrophotometry and 
spectrofluorometric procedures. It uniquely combines the inherent 
selectivity of solvent extraction and the statistical advantages afforded 
through utilization of three-component complexes. Improved sensi- 
tivity is obtained by performing exchange reactions on ion-pairs di- 
rectly in the organic extract. In the proposed method conditions are 
readily obtained whereby a weakly chromogenic or fluorogenic cation 
is replaced instantaneously by a highly colored or fluorescent dye. 
Unreacted dye is readily extracted into water, leaving only the dye 
complex in the organic phase. 

Recent studies involving nanogram amounts of gold and uranium 
have clearly demonstrated the improved selectivity and sensitivity of 
the extraction-exchange method. At least one other advantage is also 
apparent. The method shows promise of being a simple way of obtain- 
ing many new and potentially useful complexes which, heretofore, 
were impossible to prepare by conventional techniques. 

Multi-Element Analysis by Molecular Absorption Spectrophotom- 
etry — In the metals industry great emphasis has always been placed 
on the speed of analysis, with accuracy being of somewhat secondary 
importance. The increasingly stringent demands of modern day tech- 
nology, however, are creating new needs for more accurate as well as 
more rapid methods of analysis. 

Absorption spectrophotometry, while always regarded as a highly 
accurate technique, has until now been limited almost exclusively to 
single-element analysis. Recent studies, however, have shown that 
the careful selection of chromogenic reagent in combination with com- 
puter evaluation of data can yield systems and procedures that are 
equally accurate for the determination of as many as five or six ele- 
ments simultaneously. The primary prerequisites, in order of their 
importance, are degree of spectral overlap, reproducible formation, 
and stability of the metallo-organic complexes. These parameters 
have been investigated and closely evaluated in the recent develop- 
ment of a multi-element spectrophotometric procedure for the simul- 
taneous determination of cobalt, nickel, and copper. Accuracy is about 
1 percent at the part-per-million level and less than ten minutes are 
required for both analysis and computation. 

Interferometer Control for Mossbauer Spectrometer — A Mossbauer 
spectrometer uses some type of device for producing a Doppler motion 
that provides the necessary gamma-ray energy shift. Electromechani- 
cal transducers are often used, but it is important that the motion be 
measured accurately. An electromechanical system has been modified 
for control by an interferometer. The device, which uses a laser light 
source, compares an interference fringe count with standard fre- 

81 




To provide the accurate constant acceleration needed for use with, a Mossbauer 
spectrometer, this device compares an interference fringe count with a standard 
frequency, differences being used as feedback to control the motion. Constant 
acceleration is achieved by incrementing the standard frequency with time. 

quency. Any difference is detected, and a correction signal is generated 
as feedback to the electronic system. Constant acceleration is achieved 
by incrementing the standard frequency linearly with time. This ar- 
rangement provides the extreme accuracy and precision of motion 
which enables the Mossbauer spectrometer to produce spectra of un- 
precedented reliability. 

New Clean-Room Facility — A clean-room facility of advanced type 
has been designed and installed and is providing improved handling 
capability in ultratrace analysis. The facility consists of two clean 
rooms separated by a perforated wall partition, together with rooms 
to prepare personnel for entry into the clean areas. Horizontal laminar 
air flow, at an average rate of 100 lineal feet per minute, is provided 
for the clean areas. An absolute filter bank removes essentially all air- 
borne particles greater than 0.5 pm in diameter. Each cubic foot of air 
in the room adjacent to the filter bank contains less than 100 such par- 
ticles, while a particle-level less than 1,000 is maintained in the second 
room. The rooms are currently used for microscopic examinations and 
for the assembly and disassembly of apparatus when extreme cleanli- 
ness is a requisite. Two laminar-flow fume hoods permit mild chemical 
reactions to be performed under ultra-clean conditions. 



82 



Improved Trace -Chromium Determination — A method of improved 
sensitivity and accuracy has been developed for determination of as 
little as one ten-billionth of a gram of chromium. The coulometric 
method consists of titration of chromium with electro-generated fer- 
rous ion in a specially designed electrolysis cell of small volume to 
permit increased sensitivity. An improved end-point detection tech- 
nique was also devised to facilitate the analysis. The new method 
provides sensitivity and accuracy of at least an order of magnitude 
better than previously available in the low concentration range. Micro- 
gram quantities of chromium can now be determined with an accuracy 
better than one part in a thousand while nanogram amounts can be 
determined to within a few percent of the amount present. From that 
point the accuracy drops off rapidly down to a lower limit of about 
a tenth of a nanogram (one ten-billionth of a gram). The method 
should be widely applicable to trace chromium determinations ranging 
from biological and clinical materials to metallurgical products. At 
NBS, it has been used for determination of chromium in ruby laser 
using only milligram amounts of the crystal in the determination. 

Polarographic Analysis of Air Pollutants — Polarographic methods 
have been developed for the simultaneous determination of very low 
levels of iron, copper, cadmium, and lead present as air pollutants. 
Samples are collected on conventional filters which are ashed or from 
which the contaminant may be extracted by leaching* in favorable 
cases. An ammonium oxalate supporting electrolyte is used, and the 
metal is determined by fast scan polarography. For extremely low 
levels of contaminants, preelectrolysis into a hanging drop electrode 
followed by anodic stripping voltammetry is used. The submicrogram 
detection limits make possible a number of application areas. The 
methods have been applied to a wide range of air-pollution problems 
including determination of the metallic contaminants of suburban 
and semirural residential areas, and to collaborative studies with the 
National Air Pollution Control Administration. They have also been 
applied to monitoring ambient lead in a laboratory involved in glass- 
making operations, and even to the determination of metallic con- 
stituents in relatively clean laboratory air to identify sources of blanks 
in trace analysis. 

Analysis of Thin Metallic Films — Polarographic methods have been 
developed in 1MB laboratories which have become extremely im- 
portant for the microchemical analysis of thin metallic films such as 
are used in electronic circuitry. Such films must be accurately ana- 
lyzed, yet there is not sufficient material to be accurately weighed, let 
alone enough for analysis by conventional methods. The polarographic 
method consists in dissolving the film and quantitatively determining 
each constituent by electroanalytical measurement with a dropping 
mercury electrode. Methods applicable to films composed of anti- 

83 



mony-bismuth, copper-nickel-chromium-aluminum, nickel-chromium, 
lead-selenium, and lead-tin-tellurium, respectively, have been devel- 
oped to date, with total film amounting to only a few tenths of a milli- 
gram in each case. 

Ion-Selective Electrodes for Microanalysis — Ion-selective electrodes 
are becoming increasingly useful in chemical analysis, but the physical 
dimensions of these sensors have limited their applicability to situa- 
tions in which relatively large amounts of sample are available. IMR 
research on miniaturization of these sensors has resulted in two im- 
portant developments. A commercial silver sulfide ion-selective elec- 
trode has been modified for use with small samples by drilling 5- to 
10-/xl depressions directly into the poly crystal line silver- sulfide mem- 
brane of the inverted electrode. Such an arrangement permits measure- 
ments on 5 jul of sample down to the lowest detection limits possible 
with this electrode. 

The first successful truly miniature ion-selective electrode has re- 
sulted from redesign of the solid-state fluoride electrode. The construc- 
tion resembles the conventional electrode except that the lanthanum 
fluoride membrane consists of a small conical-shaped crystal sealed 
in a plastic tube drawn down to a fine point. The sample volume re- 
quirement is less than 2 /d (1/25 of a drop) and the needle-like pro- 
file of the electrode makes it adaptable to in situ, in vivo, and on-line 
continuous analysis. Further miniaturization in this manner is feasible 
and should provide electrodes of even greater versatility. 

Aqueous Boric Acid-Borate-Mannitol Equilibria — Despite wide- 
spread use and extensive research on poly alcohols, especially mannitol, 
as addition agents in boric acid titrimetry, the stoichiometry and 
equilibria involved have not been clearly established. In view of the 
importance of this procedure in the determination of boron, IMR 
chemists have reinvestigated this system. Proton nuclear magnetic 
resonance spectra of boric-acid-borate-mannitol solutions in deuterium 
oxide and electrometic pH measurements of aqueous solutions were 
consistent with the formation of both 1 : 1 and 1 : 2 borate-mannitol 
complexes. The successive formation constants of the complexes were 
found to be only slightly different (pK = -2.79; pK 2 = -2.19). Fail- 
ure to recognize this fact has led previous investigators to misintrepret 
data and to erroneous conclusions, Revaluation in light of the present 
results brings several earlier discordant findings into agreement with 
the IMR conclusions and establishes a consistent model for this im- 
portant analytical system. 

Boron isotope ayialyses — A surface emission mass spectrometric 
technique for the precise measurement of boron isotope ratios has been 
developed. A single-filament tantalum ribbon source was used, and 
]] B/ 10 B ratios were determined by measuring the relative abundances 
of Na 2 10 BO 2 + and Na 2 11 B0 2 + ions, at masses 88 and 89, respectively. 

84 



The effects of various parameters such as sample-mounting procedure, 
filament material, sample size, total sample composition, and sodiunii 
concentration were studied and alternative procedures were evaluated. 

This precise technique was used to measure the absolute isotopic 
abundance ratios of two boron isotopic standards; SRM 951, 
11 B/ 10 B=4.0362±0.00137; an( j SRM 952, 11 B/ 10 B=0.053199± 
0.000032. These standards and the new mass spectrometric measure- 
ment technique will be of significant value for the precise characteriza- 
tion of the boron used in nuclear reactors. They should also be useful 
for the characterization of isotopic variations in natural boron. 

Atomic Weight of Rubidium — The atomic weight of rubidium has 
been redetermined by solid-sample thermal emission mass spectrom- 
etry. The absolute isotopic ratio was obtained by calibrating the 
instruments used with samples of known 87 Rb/ 85 Rb ratio, prepared 
from solutions of the separated isotopes. The resulting atomic weight 
of 85.46776 ± 0.00026 is not significantly different from the old value of 
85.47 but shows a significant increase in precision. 

Solvent Extraction With Hydrogen Bis {2-Ethylhexyl) Phosphate — 
Solvent extraction is one of the most useful techniques for separating 
one constituent of a mixture from interfering substances prior to 
analysis. Alkyl esters of phosphoric acid have been shown to be excel- 
lent extractants for metallic elements. One of these esters, that of 2- 
ethylhexanol, has been used extensively for rare-earth separations. A 
comprehensive study of the extraction of all the metallic elements into 
this reagent as a function of mineral-acid concentration has been com- 
pleted. As a direct result of these studies, three new applications for 
this reagent in radiochemical separations have already been developed, 
and several other separations schemes, both for individual elements 
and for groups of elements, are under investigation. The separations 
are rapid, quantitative, and, with suitable choices of the back extract- 
ant, the mineral acid, and the concentrations, substantially interfer- 
ence-free. 

Nondestructive Determination of Impurities in Ruby Laser Crys- 
tals — The effect of trace elements on the performance of solid-state 
lasers is as yet incompletely understood. In order to make possible a 
later correlation of laser optical properties with trace-element content, 
nondestructive neutron activation analysis methods have been applied 
to determination of over 10 trace elements in ruby at the ppm and ppb 
levels, with precisions of 2 to 5 percent. The samples were irradiated 
in the NBS reactor and the trace elements determined by gamma 
spectroscopy using a lithium-drifted germanium gamma-ray detector 
of large volume and high resolution. Because of the highly refractory 
nature of the matrix, other trace-analysis techniques proved to be of 
limited applicability. These new procedures provide a definitive char- 
acterization of ruby crystals and pave the way to an elucidation of the 
relationship between composition and optical behavior. 

85 



New Applications of the C ockcroft-W cdton Neutron Generator — 
A comprehensive study of the utility of 3-MeV neutrons, from the 
( 2 H9 2 H,/i) 3 He reactions, for compositional analysis of macro con- 
stituents, has been made. This expands considerably the analytical 
application of the small neutron generator, previously limited to 
14-MeV neutron activation analysis. The study included experimental 
determination of the analytical sensitivity for more than TO elements 
along with the gamma-ray spectra from these elements. In addition 
to their direct analytical application, these results may be used for 
the prediction of interferences from the buildup of the 3-MeV neutron 
flux encountered in 14-MeV neutron activation analysis from deute- 
rium embedded in the tritium target. Thermalized 3-MeV neutrons 
from a small neutron generator were used successfully in the analysis 
of the metallic components of several oil-soluble organometallic Stand- 
ard Kef erence Materials. 

Determination of Oxygen in Sodium Metal — The corrosive nature 
of sodium metal used as a coolant in breeder reactors is markedly 
affected by oxygen content. The determination of oxygen in sodium 
by conventional methods is complicated by the possibility of surface 
contamination of the metal after sampling, yielding a result that is 
not representative of the bulk sample. In addition, the various reagents 
and equipment used may contribute to the analytical blank, and this 
blank may not be susceptible to accurate evaluation. 

Photonuclear activation analysis, in which no blank correction need 
be made, has now been applied to this determination. The reaction 
utilized was 16 0(y,?i) 15 0. To remove surface contamination, the sample 
was etched after irradiation but before chemical separation and count- 
ing. A procedure to separate the radioactive oxygen from interfering 
substances in 3% min was developed, and accurate determinations 
were achieved in spite of the very short half -life of the product nucleus 
(2.1 min). Sensitivities of a few ppm and precisions of 10 to 15 per- 
cent were obtained. 

Analysis of Surface Structure by Mossbauer Spectroscopy — Because 
the appropriate (Mossbauer) nuclear energy level of iron- 57 decays 
with a high probability of emitting conversion electrons, Mossbauer- 
effect spectroscopy provides an interesting probe with which to examine 
chemical structure of surfaces of iron bearing materials. A propor- 
tional detector has been designed to detect these ^'3 keV conversion 
electrons. The design has been optimized to provide the maximum 
signal to background ratio. 

Gas-Water Chromatography — The use of aqueous solutions as the 
liquid phase in gas-liquid chromatography has been developed into a 
practical, rapid method of analysis. Techniques have been developed 
to compensate for the tendency of the solutions to volatilize during 
the analysis, and thus change composition. As a result, the vast body 

86 



of information on equilibria in water solutions can be applied to the 
design of chromatographic columns. Effective separation of the deu- 
terated ethylenes C 2 D 4 , C 2 H 2 D 2 from C 2 H 4 has been achieved. The 
technique also can be used to determine gas-water partition coefficients 
and equilibrium constants for reactions occurring in aqueous solutions. 

Mechanism of Steric Exclusion Chromatography — Steric exclusion 
chromatography, also called gel filtration or gel permeation chro- 
matography, has in recent years become a powerful tool for the sepa- 
ration and analysis of large molecular species such as synthetic high- 
polymers, biopolymers, viruses, etc. Although widely applied, the 
precise mechanism of the separation process is not fully understood. 
This is partly due to the difficulties in measuring the pore size distri- 
bution of the gels which so far have been used with the method. By 
replacing the gels with glasses of precisely controlled and measurable 
pore size, the separation process was studied under controlled condi- 
tions. The results challenge the validity of the two presently most 
popular separation theories. The use of porous glass as separation 
medium is of further value to test present theories of the molecular 
conformation of macromolecules in solution. 

Long range Atomic Ordering in Platinun- group Alloys* — In many 
alloys containing tw r o or more metals, the atoms of each element tend 
to occupy special positions over large regions within the crystalline 
lattice. This behavior can usually be produced by an appropriate heat- 
treatment at relatively low temperatures. The alloy is then described 
as possessing long-range atomic ordering. The extent of long-range 
atomic ordering can be measured by studying the relative intensities 
of x-ray beams diffracted by the crystal. A comprehensive study of the 
degree of long-range atomic ordering in a variety of binary alloys con- 
taining metals of the platinum family has revealed that the location 
of a given element in the periodic table can be related to its tendency 
toward atomic ordering. 

The degree of long-range atomic ordering in an alloy often has a 
very significant effect on the mechanical properties of the alloy ; par- 
ticularly its strength and hardness. By intentionally varying the de- 
gree of atomic ordering, one can obtain desirable properties in dental 
gold alloys for example. 

In a recent cooperative study with other laboratories it was found 
that changes in the degree of atomic ordering also produce significant 
changes in the temperature at which certain metal compounds (A15 
phases) lose their electrical resistance completely and become super- 
conductors. This discovery may have important implications since 
there is presently an intensive effort in many countries to develop 
alloys which would permit the economic utilization of superconductors 
to transmit electrical power. A basic understanding of the factors 
which control atomic ordering may permit the attainment of this goal. 

87 



It may also help to improve the properties of alloys now being used 
for dental and medical applications. 

Low Angle X-Ray Diffraction Intensities in N -Paraffins — Problems 
concerning the structure and thermal behavior of the interlamellar 
regions of crystalline chain-folded polymers and ^-paraffins have been 
studied with x-ray diffraction techniques. The x-ray diffraction from 
the crystalline ^-paraffins, C 36 H 74 , C 44 H 90 , and C94H190, was examined 
at small angles as a function of temperature. The Bragg maxima 
(doo ) that occur at low angles result from a lamellar repeat distance 
which depends on the molecular length. In general, the intensity of 
these maxima was found to increase with increasing temperature in an 
approximately reversible manner. All the samples experienced solid- 
solid phase transitions in the temperature range of observation. Sev- 
eral possible mechanisms consistent with the temperature dependence 
of the intensity have been analyzed. 

Polywater — In a collaborative study with the University of Mary- 
land, a different form of water has been verified and has been shown 
to have a unique molecular structure. The interpretation of the in- 
frared and Raman spectra indicates that this material is a stable 
polymer consisting of ordinary water molecules. This new form of 
water has been named polywater. 

Polywater has properties remarkably different from those of normal 
water. Although polywater maintains the same chemical composition, 
it has a thermal stability to temperatures of the order of 500 °C; has 
a very low vapor pressure ; has a density about 40 percent higher than 
ordinary water, and begins to solidify at —50 °C or lower to a glass- 
like state. 

Several molecular structures for polywater have been proposed. 
These structures are consistent with the infrared and Raman spectra 
as well as with the properties, bonding, and the stability of the mate- 
rial. The infrared spectrum is unique: the O — H stretching bands 
prominent in normal water are absent and two new strong bands 
appear. One of the proposed structures shows that the O — H — O units 
are arranged in a plane and form hexagonal rings. 

Crystallography of Calcium Phosphates and Related Compounds — 
Phosphorus in general and calcium phosphates in particular are very 
important in the life of vertebrates. Among the calcium phosphates 
found in the human body, either as skeletal material or pathological 
deposits, are Ca 5 (P0 4 ) 3 (F, OH), Ca 8 H 2 (P0 4 ) 6 -5H 2 0, /?Ca 3 (P0 4 ) 2 
and CaHP0 4 -2H 2 0. CaHP0 4 and aCa 3 (P0 4 ) 2 are other important 
and relevant structures. The structures of aCa 3 (P0 4 ) 2 and /?Ca 3 (P0 4 ) 2 
are unknown and may be extremely difficult to determine. The crystal 
structures of the related compounds Ca 5 (P0 4 ) 3 Si0 4 and Ca 4 Mg 5 
(P0 4 ) 6 were determined. These structures apparently have close and 
revealing relationships to Ca 5 (P0 4 ) 3 (F, OH) and K 3 Na(S0 4 ) 2 , in 

88 



L 






nflPV 





Proposed structures for polywater are discussed by members of the 
University of Maryland team investigating this material. 



1 

l? I 

NBS- 



the case of Ca 5 (P0 4 ) 2 Si0 4 and to K 3 Na(S0 4 ) 2 , aCa 3 (P0 4 ) 2 , and 
ySCa 3 (P0 4 ) 2 in the case of Ca 4 Mg 5 (P0 4 ) 6 . 

Analysis of the Shapes of Polycyclic Carbohydrate Molecules — 
The shapes of organic molecules are important to an understanding 
of their reactions. Most carbohydrates occur in cyclic nonplanar forms, 
but the forces that determine which of several different possible shapes 
each favors are not well understood. In this work, the shapes of 
sugar molecules formed by joining together several rings composed of 
five or six atoms have been studied by nuclear magnetic resonance 
techniques with computer analysis of the data. Assignment of the 
total shape of the molecules was aided by newly developed mechanisms, 
by which an excited nucleus can transfer radiofrequency energy to 
other nearby nuclei. The results show that electrostatic forces have 
an important influence on molecular shape. 

Determination of Orosslinked Organic Networks — Three-dimen- 
sional organic network polymers have been available for several 
decades, but there have been serious impediments to the determina- 



89 



tion of their molecular structures. The copolymers of styrene and 
divinylbenzene are intermediates in the preparation of the derivative 
ion-exchange materials. Previously, it has been impossible to measure 
the styrene/divinylbenzene ratio after these compounds have reacted 
together. This problem has been solved by studying the infrared 
spectra of the copolymers. Comparison was made to similar spectra 
taken of NBS Standard Reference Material No. 705, polystyrene. 
The study revealed the presence of aromatic hydrogen (out-of -plane 
bending) vibrations, and these features have been identified with the 
corresponding divinylbenzene cross-linking agent. Measurement of 
cross-linking in the copolymer is thus feasible, and high-speed compu- 
tation methods are being developed in order to do this with high 
accuracy. 

Reduced Crystallographic Cells — Methods to obtain a unique re- 
duced cell, once the three shortest noncoplanar lattice translations 
are known, have been developed in this laboratory. This work was 
undertaken because in addition to their theoretical interest, reduced 
cells have two important applications in crystallography: (a) they 
make it possible to determine the Bravais lattice from an arbitrary 
primitive cell of the lattice, (b) they provide a method for the clas- 
sification of crystalline substances, 

(a) Determination of the Bravais Lattice — If any primitive recip- 
rocal cell can be derived from the x-ray diffraction patterns, then the 
corresponding direct cell, which is also primitive, can be reduced. 
The Bravais lattice can be determined from a table which relates the 
44 reduced cell types to the Bravais lattices. The use of the reduced 
cells saves much of the preliminary work normally needed in crystal- 
structure analysis. The application of the reduced-cell concept be- 
comes especially useful when crystals are grown and studied under 
special conditions, such as high pressure and high or low temperature, 
when it is difficult or impossible to determine the lattice symmetry 
by conventional means. Reduced cells will be applied to high-pressure 
diffraction studies and to the determination of crystal symmetry with 
computer-controlled diffractometers. 

(b) Classification of Crystalline Substances — The present deter- 
minative listing of crystalline substances is made on the basis of cell 
dimensions within each crystal system. The choice of a conventional 
cell dictated by lattice symmetry is possible in all crystal systems 
except triclinic and monoclinic. The use of the reduced cell, however, 
makes it possible to classify uniquely all crystals including those crys- 
tallizing in the triclinic and monoclinic systems. The use of reduced 
cells has been applied to triclinic crystals. 

Single-Crystal X-Ray Diffraction at High Pressure — The first suc- 
cessful structure determination by single-crystal diffraction techniques 
of a high-pressure polymorph in its region of stability has been com- 

90 



pleted. The study was conducted on benzene, an extremely important 
chemical material. Benzene is a liquid under ordinary conditions but 
crystallizes at about 5 °C. at ordinary pressure. The structure of this 
crystalline form has been studied extensively at low temperatures by 
conventional x-ray and neutron diffraction techniques. The crystal is 
orthorhombic and has a surprisingly complex arrangement of benzene 
rings. Benzene can be crystallized at room temperature at about 
0.6 kbar and it was found that the crystal structure is the same as that 
obtained at low temperatures. This form is denoted benzene-I. If the 
pressure is raised on benzene-I, it transforms above 12 kbar to a denser 
crystalline form known as benzene-II which is stable only under 
high pressures. This crystal was the object of the present studies. 

Single crystals of benzene-II were grown in the beryllium high-pres- 
sure diamond anvil cell and studied by precession x-ray diffraction 
techniques. Considerable effort was expended in an unsuccessful at- 
tempt to find the structure of the first crystal of benzene-II. The lack 
of success forced the conclusion that the intensity data should be 
checked using a different crystal. Several new crystals of benzene-II 
were grown and studied and although all crystals showed similar recip- 
rocal lattice networks, the first crystal appeared to have a higher sym- 
metry than subsequent ones. It was concluded that the original crystal 
was highly twinned. Data from the other crystals showed benzene-II 
to be monoclinic and the structure was readily obtained using com- 
puter techniques developed for use on the original crystal. In the new 
structure the benzene rings are packed more tightly than in benzene-I 
and are oriented more nearly parallel. The structure obtained by the 
diffraction studies was shown to be that arrangement producing the 
lowest repulsive energy between the closely packed rings. The struc- 
ture obtained could not have been deduced by any other available tech- 
niques — i.e., powder diffraction — because of the low crystal symmetry 
and the low scattering-power of the benzene molecule, 

Accurate Cell Parameter Data, from Small Single Crystals — An 
existing x-ray diffractometer has been extensively modified to facili- 
tate making more accurate cell parameter measurements than can 
normally be made with small (0.1 mm) single crystals. Because the in- 
strument is intended for use with "ordinary-' crystals which generally 
have sufficient mosaic character to limit the attainable precision, very 
high accuracy is not expected. The real value of the modification is in 
preparing crystals for intensity measurements with the automatic dif- 
fractometer. In this way the need for using the latter instrument for 
time-consuming hand measurements in order to establish cell param- 
eters and orientation can be eliminated. Specimen temperature control 
is planned which will facilitate measurements of anisotropic thermal 
expansion on a wide variety of crystals. Use of a diamond-anvil high- 
pressure cell for measurements of cell parameters as a function of pres- 
sure is also being considered. 

375-572—70 -7 91 



X-Ray Powder Diffraction Data — A program for the calculation 
of x-ray powder patterns has been started at IMR, and is part of the 
project for extending and improving data for use in the identification 
of crystalline phases. Patterns are calculated when it is impractical 
to produce experimental data because of the nonavailability of a good 
sample or because of experimental difficulties. Using the published 
data from the general literature, the 6?-spacings and relative intensi- 
ties are calculated. 

The intensities are computed as relative peak heights and simulate 
closely those results which would be obtained experimentally with a 
diffractometer and Cu radiation. Calculations are only made from 
highly reliable structural data. The results are published in the NBS 
Monograph Series of Standard X-ray Diffraction Powder Patterns 
and are also included in the Powder Diffraction File of the American 
Society for Testing and Materials. 

Electron Microscopy of Rocks— Geologists studying the mechanics 
of deformation of rocks from the earth or the moon have used optical 
microscopy to observe deformation textures in their materials. In 
collaboration with the Geology Department of U.C.L.A., the 
feasibility of using transmission electron microscopy for studying 
geological materials was explored. The experimental conditions 
simulating rock deformation involve testing under high confining 
pressures and elevated temperatures. With brittle materials such as 
quartz, the test specimens and also the natural samples often are frac- 
tured and recrystallized indicating severe deformation. In order to 
prepare samples for study by electron microscopy, special thinning 
techniques were needed. Such techniques have been developed and 
used for many ceramic materials at NBS. By using ion bombardment, 
thin foils suitable for transmission electron microscopy were prepared 
from petrographic thin sections. Dislocation arrangements associated 
with plastic deformation in quartz rocks were observed directly ; and 
some of the results were compared with observations made by optical 
microscopy. 

Effect of Impurities on the Crystal Structure of Tantalum 
Pentoxide — Oxide compositions containing tantalum and other cations 
of similar size have been investigated at high temperatures. The small- 
est cations have been found to stabilize low temperature forms of 
Ta 2 5 whereas slightly larger cations were found to stabilize the high 
temperature polymorph. Crystal structure analysis of the high-tem- 
perature form has revealed a completely new structure type. The 
crystal structure of the low -temperature form was found to be depend- 
ent upon the amount of smaller cations added to Ta 2 5 and upon the 
total stoichiometry. Both play an important role in determining the 
number and type of polyhedra necessary to make up a unit cell. 

92 



Lattice Defects in A1 2 3 by Transmission Electron Microscopy — 
At low temperatures aluminum oxide is generally regarded as a purely 
brittle material with plastic deformation due to the generation and 
movement of dislocations possible only at temperatures in excess of 
900 °C. However, by using an argon ion-bombardment technique to 
thin specimens in a controlled manner for examination in the electron 
microscope, it has been shown that plastic deformation does occur 
under hardness indentations at room temperature and that mechanical 
polishing introduces a high density of dislocations within a surface 
layer less than one micron thick. Direct evidence for plastic deforma- 
tion at temperatures less than 900 °C has not been reported previously. 
Although the large-range movement of dislocations does not appear 
possible at low temperatures, the presence of such high densities of 
dislocations in the surface regions of mechanically polished single and 
polycrystalline samples of aluminum oxide is expected to alter their 
mechanical, optical, and chemical properties and, therefore, must be 
taken into consideration. 

Because of their relatively high strength and chemical inertness 
even at high temperatures, ceramic materials such as aluminum oxide 
are important structural materials. Studies on the mechanical prop- 
erties are, therefore, essential and a more complete understanding of 
these properties can be obtained by detailed investigations of lattice 
defects, such as dislocations, and their role in the deformation process. 
Since lattice defects also affect the optical properties, these studies 
are important to materials with laser applications. 

New Diffraction Theory for Imperfect Crystals — A crystal which 
contains imperfections — such as dislocations, defects and impurities — 
diffracts xrays to give fine structure detail in the diffracted beams 
which represents topographic images of the imperfections. The in- 
tensity of the diffracted beams also changes from the dynamical value 
to the kinematical value (known as the extinction effect), depending 
on the degree of crystal imperfection. 

Until recently there has been no theory to explain the topographic 
images and the change in diffraction intensities (the extinction effect) 
in terms of the properties of existing imperfections. For example, the 
existing extinction theory requires the famous mosaic block model to 
represent crystal imperfections. 

A new dynamical diffraction theory for imperfect crystals has been 
developed by IMR scientists. The theory has been derived from a quite 
general view of scattering. The ordinary dynamical theory, which is 
valid only for a perfect crystal, is merely a special case in this new 
dynamical theory of diffraction. Establishing such a theory is impor- 
tant, not only for determining the properties of crystal imperfections 
in a real crystal, but for crystal -structure determination with single 
crystals, where the extinction effect is the most difficult factor to 
estimate. 

93 



Characterization of a Hexagonal Alloy— A series of hexagonal 
silver-tin alloys has recently been characterized in terms of the defect 
dislocation structures and the stacking fault energy, using the tech- 
nique of transmission electron microscopy. The electron microscope 
permits the direct observation of individual dislocations and stacking 
faults. Alloys having several different compositions were plastically 




m 



k : ^iM^ 




An example of the dislocation structures found on close-packed crystal planes in 
a silver-tin hexagonal alloy is seen in this transmission electron micrograph. 
Several examples of close-spaced dislocation multiplies are present, interact- 
ing with two distinct sequences of glide dislocations produced by plastic 
deformation. Af=30,000X. 



94 



deformed to introduce dislocations, then examined. The studies con- 
centrated on the variation in stacking faults energy with alloying, and 
on the importance of the several different dislocation glide systems 
(hat operate. Interactions betwen different groups of dislocations were 
studied and the results interpreted in terms of the known mechanical 
behavior. 

Dislocations in Crystals— One way in which dislocations contribute 
to the mechanical properties of materials is as sources of residual or 
internal stress. A general theory of static sources of internal stress has 
been developed for finite anisotropic elastic bodies, including struc- 
tures with complex topology. Using a projection formalism, the 
stresses and strains due to dislocations and "welded in' 1 sources of 
internal stress have been calculated. 

Another crystalline defect, a source of internal stress of somewhat 
higher complexity than the dislocation, is the disclination. A linear 
continuum theory of continuous distributions of static disclinations 
has been developed for the first time. This theory also relates to other 
developments in continuum mechanics. 

STANDARD REFERENCE MATERIALS 

From a beginning in 1906 with four standard samples of cast iron, 
the NBS Standard Reference Materials Program, which made the 
United States the first country with a national program of this kind, 
has grown to the point that almost 700 different SRM's are now pro- 
duced or are nearing completion. These include 8 new categories avail- 
able for the first time this year — labelled organic compounds, 
electrical and magnetic standards, ion activity standards, electron 
microprobe standards, certified analyzed liquids, high-purity metal 
standards, certified gas standards, and electronic and magnetic al- 
loys — in addition to the 70 categories already available. These are the 
result of the continuing effort to keep the Standard Reference Ma- 
terials program abreast of the growing and changing needs of the 
times. 

This year has been one of continued growth and expansion of the 
SRM program. Maintaining a balance between providing renewal 
SRM's for industries which now rely heavily on SRM's, and respond- 
ing to new national needs in areas such as health, air and water pollu- 
tion, resources development and the like, has been difficult. That some 
balance has been achieved is indicated by the fact that during 1968, 
66 new and 74 renewal SRM's were issued, and 54 SRM's were dis- 
continued because the need for them had diminished or new SRM's 
were judged to better serve the overall interests of the Nation's science 
and technology. There were in stock at the end of 1968, 651 different 
items in 59 distinct categories totaling over 380,000 units. Work in 

95 



progress to produce 318 new and renewal SRM's was centered in 146 
projects. Sales during this calendar year to 8,000 customers totalled 
just over $1,000,000. 

Examples which follow have been selected from the 44 new and 
21 renewal SRM's completed and certified during fiscal year 1969 by 
13 technical divisions of NBS. 

High-Purity Metals— SRM 685— & new high-purity gold SRM was 
issued in wire form for spark-source spectrometry, in rod form for 
other methods of characterization and for reserach which requires a 
high-purity, homogenous standard material. 

A high-purity gold vapor pressure SRM (SRM 745) also was issued 
for which the vapor pressure was accurately determined over the 
pressure range of 10~ 3 to 10~ 8 atmospheres and over the temperature 
range 1300-2100 °K. 

The high-purity gold is issued with a Certificate of Analysis which 
gives "state of the art" information on the chemical composition, in- 
cluding values for coper, indium, iron, oxygen, and silver. Estimated 
limits of concentration are provided for 21 other elements which were 
detected by spark-source mass spectrometry. Extensive homogeneity 
testing was performed to establish that the gold was satisfactory 
within the precision of the analytical methods used. These included 
neutron activation, polarography, spectrophotometry, spark-source 
mass spectrometry, isotope dilution, and vacuum fusion in addition to 
optical emission spectrochemical analysis and residual resistivity ratio 
measurements. 

The gold vapor-pressure SRM represents the first in a series of ele- 
ments which will be certified for vapor pressure in the 10~ 3 to 10~ 8 
atmosphere range. The series will cover the temperature range 600 to 
3000° K. 

In the field of high-temperature vapor pressure measurements there 
has been a need for standards. It is not uncommon for vapor-pressure 
measurements made by experienced investigators to differ by 30 per- 
cent, 50 percent, or even 100 percent. The gold vapor-pressure SRM 
was developed for use in the testing and calibration of vapor-pressure 
measurement apparatus and techniques, and for use in the detection 
of possible systematic errors. It also can be used for direct interlabora- 
toiy comparisons. The homogeneity of the gold was confirmed by 
extensive testing. 

Biomedical Standards: SRM 912, 913, 9U, 915— Four additional 
NBS Standard Reference Materials were certified as chemicals of 
known purity for use in calibration and standardization of procedures 
used in clinical laboratories. These supplement cholesterol, which was 
made available previously. The new SRM's are : urea, certified at 99.7 
percent purity ; uric acid, certified at 99.7 percent purity ; creatinine, 
certified at 99.8 percent purity, and calcium carbonate, certified at 99.9 

96 



percent purity. The value of the purity of each of these SRM's has an 
estimated inaccuracy of 0.1 percent. 

The homogeneity of each of the lots from which these standards 
were prepared was tested and proved satisfactory by chromatographic 
and spectrometric techniques. These methods also showed the mate- 
rials to be free of measurable amounts of organic impurities, with 
the exception of a small amount (<0.07 percent) of biuret in the 
urea. 

Spectrometric analyses of the ash obtained from each of the first 
three of these SRM's indicated only minor concentrations of the several 
metallic elements found. These results were substantiated by neutron 
activation analyses of the bulk materials. 

The purities of the urea and creatinine were determined by phase- 
solubility analysis, and for the former, was also confirmed by differ- 
ential-scanning calorimetry. The purity of the creatinine was further 
evaluated by setting limits on amounts of possible impurities that 
would be undetected by the chromatographic and spectrometric tech- 
niques employed. No organic impurities could be detected in the uric 
acid even after the application of techniques that should have con- 
centrated the impurities, had they been present. 

The calcium carbonate is a very high-purity material intended for 
use as a standard for all clinical determinations of calcium. Like the 
other four SRM's in the series it was prepared at the request of the 
College of American Pathologists and the American Association of 
Clinical Chemists. They placed a high priority on the certification 
and issuance of the calcium standard. 

The rapid and accurate analysis of calcium in serum is an important 
clinical test. Hypercalcemia, when supported by other clinical evidence, 
is often indicative of hyperparathyroidism, and medical decisions in- 
volving immediate surgery are often made on the basis of the serum 
calcium value. The imperative need for accurate calcium determina- 
tions is obvious. 

In clinical procedures, calicum is determined, usually as a calcium- 
fluorescent complex, by fluorometry, by flame emission, or by atomic 
absorption methods. The NBS calcium carbonate SRM will serve as 
the primary standard for the calibration of the instruments and 
methods used. 

The material was examined for compliance with the specifications 
for reagent-grade calcium carbonate as given in Reagent Chemicals, 
4th edition, published by the American Chemical Society. The mate- 
rial was found to meet or exceed the minimum requirements in every 
respect. Examination by thermal gravimetric analysis indicated the 
loss of a minute proportion of weight below 175 °C (volatile matter), 
and the composition was stable above this temperature up to a temper- 
ature of 625 °C, above which decomposition (evolution of C0 2 ) set in. 

97 



Replicate samples taken from a randomly selected region of the 
undried material were assayed by a coulometric acidimetric proce- 
dure, The results from nine independent determinations, based on 
expression of the assay as calcium carbonate, indicate a purity of 
99.99+ percent with a standard deviation of 0.003 percent, Samples 
equilibrated at a relative humidity of 90 percent and assayed by this 
coulometric procedure showed a maximum moisture absorption of 
0.02 percent as compared to samples that were dried for 6 hours at 
210 °C. The moisture content on samples equilibrated at 75 percent 
relative humidity was found to be 0.01 percent. This water content 
was determinated by the Karl Fischer method. 

A semiquantitative survey for trace contaminants by emission 
spectroscopy indicated the presence of less than 0.001 percent of copper, 
iron, magnesium, manganese, and silicon in the material. By atomic 
absorption, magnesium was evaluated at 1.0, sodium at 0.4, and 
strontium 2.1 ppm ; potassium was less than 0.4, lithium less than 0.05, 
and barium much less than 10 ppm. Neutron activation analysis indi- 
cated copper 0.9, manganese 0.6, and sodium 0.5 ppm. Copper was 
determined at 1 ppm by spectrophotometry. 

Electronic and Magnetic Alloy Standards: SRM 1159, 1160 — Two 
new nickel-base SRM's — widely used in the electronic and magnetic 
industries — were made available. One is a nominal 49 percent nickel, 
balance iron alloy, and the other is a nominal 80 percent nickel, 4 per- 
cent molybdenum, balance iron alloy. 

These two new SRM's were issued meet a serious deficiency of stand- 
ards for both producer and consumer of electronic and magnetic alloys. 
It is estimated that by 1975 the use, e.g., of permanent magnets will 
double from the present annual $50 million market. Permanent mag- 
nets are in wide use in such applications as battery operated hand tools 
for home use, motorized garden and kitchen equipment, etc. These ap- 
plications and others, where permanent-magnet motors are preferred 
for reasons of reliability and efficiency, are on a steeply rising growth 
curve. 

Designed primarily for calibration in optical emission and x-ray 
spectrometric methods of analysis, the standards were issued in disk 
form I14 in. (3.1 cm) in diameter and % in. (1.9 cm) thick. Lathe chips 
may easily be prepared from the disks in the user's laboratories, if 
desired, for checking chemical methods of analysis both for production 
control and for customer acceptance. 

The material for the standards was prepared in a vacuum induction 
furnace and supplied to NBS in final form following a scheme of 
fabrication designed to produce material of the highest possible 
homogeneity. 

Extensive homogeneity testing was performed in the Institute for 
Materials Research, and both materials were found to be satisfactory 
within the limits of precision of the analytical methods employed. 

98 



The standards were issued with a Provisional Certificate of Analysis 
certified for carbon, manganese, phosphorus, sulfur, silicon, copper, 
nickel, chromium, molybdenum, cobalt, and iron. 

Ferrous Materials Standards: SRM 178, 1093, 1004, 31^0— A new 
chip-form carbon steel SRM was the first steel made by the basic oxygen 
furnace process to be certified. Two new steel SRM's were certified for 
oxygen and nitrogen and a new ferroalloy ferroniobium for niobium 
and other elements of interest. 

The basic oxygen steel is a plain carbon grade. This was the first 
type to be certified by NBS as Standard Reference Materials. These 
first SRM's included steels produced by the acid Bessemer, the acid 
open-hearth, and the basic open-hearth furnace processes. A strong 
demand for these standards has existed for a period of more than 60 
years, and has increased rapidly in recent years. The more stringent 
chemical-composition specifications in the steel industry and new, more 
rapid kinds of analytical equipment that rely on comparison tech- 
niques with standards of known composition are responsible for this 
demand. Furthermore, the demand is expected to grow with the con- 
tinuing growth in use of both the basic oxygen furnace and the con- 
tinuous-casting processes of steel manufacture. These relatively new 
commercial processes place urgent demands on the analytical labora- 
tory for data within a very short elapsed time from sampling to the 
reporting of the final analysis. 

The primary consideration in preparing steel Standard Reference 
Materials is the resultant chemical composition of the steel, not the 
method by which the steel is produced. This is fortunate, for in the 
United States, the acid open-hearth process is no longer used com- 
mercially, the use of the acid Bessemer process is rapidly diminishing, 
and the basic open-hearth is being superseded or supplemented by 
basic oxygen and electric furnaces. In the near future, steel for pre- 
paring renewal standards of the plain carbon steels may be available 
most readily from the basic oxygen furnace process. 

The new SRM 178, chip form, carbon steel is intended for the same 
purposes for which the Acid Open Hearth Steel SRM 20f was used. 

The role of oxygen and nitrogen as they affect the basic properties 
of metals — e.g., brittleness, ductility, etc., — is well established. A 
maraging steel can be produced which is dimensional ly stable; oxygen 
present as inclusions affect this stability, especially in high pressure 
applications. It is therefore important that SRM's be available with 
known oxygen and nitrogen content to calibrate the various instru- 
ments or methods now used to determine these gases. 

The two new SRM's certified for oxygen, SRM 1093 and SRM 
1094, also have supplemental information given on the nitrogen con- 
tent. A revised certificate of analysis w y as issued for SRM 1090, Oxy- 
gen in Ingot Iron, SRM 1091, Oxygen in Stainless Steels, and SRM 

99 



1092, Oxygen in Vacuum Melted Steel. For these three SRM's, oxygen 
values obtained by neutron activation and inert-gas fusion are included 
to support the values obtained by vacuum fusion and used on the previ- 
ously issued certificate of analysis. 

SRM 1093, with a value of 60 ±5 ppm for oxygen (certified) and 
a nitrogen value of 4807 ±10 ppm (not certified), is intended pri- 
marily for use as a standard for the neutron activation method for 
determining oxygen in steel. The oxygen was determined in a 2-inch- 
length of rod cleaned ultrasonically for 30 min in trichlorethylene, 
then dried in dry nitrogen. The rods were activated, together with 
standards of known oxygen concentration, in the NBS 14 MeV neutron 
generator. 16 N (7.2 s half-life) formed from the 16 O(n,p) 10 N nuclear 
reaction was counted and the induced radioactivity compared to that 
of the irradiated standard. 

The determination of oxygen in this particular steel by vacuum 
or inert-gas fusion is difficult because of the gettering action of the 
manganese which is of the order of 9 to 10 percent. 

Although not certified at this time, nitrogen at 4807±10 ppm was 
determined by a pressure bomb-distillation-indophenol-titrimetric 
method. Determination by vacuum fusion gave a value of 3540 ±76 
ppm of nitrogen. It is believed that the higher value is the more 
accurate. 

The maraging steel, SRM 1094, is intended for the determination 
of oxygen. The low value of oxygen, 4 ±0.4 ppm, makes determination 
by neutron activation difficult; present configuration of the NBS 
neutron generator precludes an accurate determination of oxygen at 
this level. Redesign of the equipment to increase the sensitivity of the 
technique at these low levels is now underway at NBS. 

The vacuum-fusion oxygen value is the result of 60 determinations 
on 12 samples of the standard. One-gram samples were carefully cut 
from the rod material, cleaned, washed and dried. A furnace tempera- 
ture of 1675 °C and a vacuum of <10~ 5 torr was maintained during the 
4 min collection time from a high-purity nickel bath. 

The nitrogen content, not certified at this time, was found to be 
70.7±3.2 and 61 ±1 ppm for the pressure bomb-distillation - 
indophenol-photometric method and vacuum fusion technique, 
respectively. 

Three SRM's— 1090, 1091, and 1092— were certified for oxygen in 
March 1966. Since that time the inert-gas fusion and neutron activa- 
tion methods have been studied and applied to the analysis of oxygen 
in these three SRM's. The results of this study are summarized on a 
revised certificate of analysis, together with the certified oxygen values, 
which remain essentially unchanged, but which are now supported by 
the additional analyses provided by the aforementioned methods. 

Additional information on the nitrogen values of these three SRM's 

100 



is also provided, but the values were not certified. The nitrogen values 
were arrived at by four different analytical methods. 

From the nitrogen results on the five SRM's, it was apparent that 
systematic biases exist in one or more or possibly all of the methods 
used for determining nitrogen. There was some evidence that nitro- 
gen results by one or more of the methods are material-dependent. 
The complexity and magnitude of this effect is not now known. A 
comprehensive research effort is underway at NBS to resolve this 
question and to search out other possible systematic errors. When 
this research is completed these standards will be certified for their 
nitrogen contents. 

At the request of the ferroalloy producers and Division F of ASTM 
Committee E-3, a ferroniobium, SRM 340, was prepared. The new 
SRM complements the list of other steel-making alloys that are avail- 
able from NBS. Ferroniobium is an important innoculant in the steel 
production process, which is rinding increasing use not only in stainless 
steel as a carbide-stabilizing element but also in carbon steels for pur- 
poses of hardenability. The ferroniobium standard certified as to its 
chemical composition is vitally important to the iron and steel in- 
dustry since the ferroalloys are largely bought and sold on a contained 
basis for the alloy constituent. On the basis of analyses performed by 
NBS and by a number of cooperating laboratories, the new SRM is 
certified for niobium, tantalum, titanium, carbon, manganese, phos- 
phorus, and silicon. 

Computer Amplitude Reference Tape Standard: SRM 3200 — An 
amplitude reference magnetic tape for use in the signal amplitude 
calibration of computer tape standard recording and reproducing 
systems was made available as a new SRM. 

The characteristics of present-day magnetic computer tapes are the 
result of long-term research and development by the magnetic tape 
industry. Technological developments in related fields, and trans- 
ducer-tape interplay, have stimulated continuing improvement of the 
tape media and its performance. This has often led to differences in 
tape characteristics and marginal operation when tapes are inter- 
changed between systems. The only tapes previously available for 
quality assurance purposes have been industry-supplied standards. 

At the request of industrial users of computer tape, Government 
procurement agencies, producers of magnetic computer tapes, and 
producers of tape-handling equipment, NBS has developed tape- 
measurement methods and will supply a "Secondary Standard Mag- 
netic Tape-Computer Amplitude Reference," through the NBS Office 
of Standard Reference Materials. 

This new material, consists of a 600-ft length of secondary reference 
tape, applicable test and calibration data, and a description of the 
equipment and procedures employed for measurement of the tape. 

101 



The secondary tapes themselves are y 2 -in wide unrecorded magnetic 
computer tapes wound on 8%-in diameter precision reels. 

Each tape will be calibrated in terms of 100 percent signal level, 
referred to the NBS Master Standard Magnetic Tape — Computer 
Amplitude Reference, which will be kept in repository at NBS. This 
signal-level calibration will be made at recording densities of 200, 556, 
800, and 3200 flux reversals per inch, and calibration information in 
the form of signal output charts recorded near each edge and at the 
center will accompany each tape. A set of saturation curves relating 
the reproduce head output voltage (on the first read-after- write pass) 
to the write current at each bit density of both the NBS Master and 
each secondary tape will also be included. The write current will 
range from zero to at least 150 percent of the saturation current level. 
The measurement processes are being described in an NBS Special 
Publication. 

Presently, the main criteria for the selection of amplitude refer- 
ence tapes for calibration as secondaries are signal-amplitude uni- 
formity and proximity of read-after-write output voltage to that of 
the Master. The instantaneous track-to-track variation in the average 
signal amplitude is limited to a maximum of 3 percent among the 
outputs from the NBS test tracks 2, 5, and 8. The location of these 
tracks is defined in ANSI Document X3.22-1967. The maximum vari- 
ation in the longitudinal average signal output voltage along each test 
tract is limited to 4 percent over the 600-f t length of tape. The absolute 
value of the avearge signal amplitude from each test track is within 
10 percent of the NBS Master Standard Magnetic Tape-Computer 
Amplitude Reference. These criteria are applied for saturation current 
recording on degaussed (fully AC-erased) tape only. 

Plutonium Assay Standard: SRM 9^4 — The Office of Standard 
Reference Materials made available a new standard reference mate- 
rial, plutonium sulfate tetrahydrate, containing 47.50 percent of plu- 
tonium. This material was issued to provide a secondary standard for 
the assay of plutonium materials to supplement the presently issued 
plutonium metal standard. Each unit of the new SRM contains the 
equivalent of 0.5 g of plutonium. 

Plutonium is a fissile material having impact on peaceful uses, 
particularly in power reactors, as well as military applications, of 
nuclear energy. Accountability problems are especially severe and will 
become even more so with the passage of time. The estimated inventory 
of plutonium by 1973 from domestic licensed facilities is 12,200 Kg. 

Because of the stringent requirements for handling plutonium metal, 
the plutonium sulfate should prove to be particularly attractive for 
assay work requiring an accuracy of the order of 0.1 percent. The 
material is relatively insensitive to humidity at room-temperature 
over the range from to 90 percent relative humidity, and provides a 

102 



solid from which appropriate-sized subsamples can be weighed easily 
for any particular use. 

Electron Micro probe and Microchemical Standards: RM Jf80, 
481, 482— The first three standards designated specifically for appli- 
cation to electron probe microanalysis were issued by the Office of 
Standard Reference Materials. 

The first of these, a composite consisting of a tungsten-20 percent 
molybdenum alloy wire core embedded in a pure molybdenum rod onto 
which there had been electro-plated a layer of pure tungsten was 
prepared through the use of powder metallurgy. High-purity metal 
powders were used to produce a standard of the maximum homogene- 
ity. Based upon the results of approximately 1,500 determinations of 
both tungsten and molybdenum by the electron microprobe, the mate- 
rial was found to be of high homogeneity of about the micrometer level 
of spatial resolution. A number of microprobe studies on this standard 
were made in IMR, including: (1) correction of the relative -intensity 
ratios to obtain concentrations in terms of input parameter uncertain- 
ties such as mass absorption coefficients and electron backscatter 
factors, and (2) effects of operating voltage on the microprobe absorp- 
tion and atomic number correction. 

Companion sets of six gold-silver and six gold-copper SRM's were 
certified for chemical composition and homogeneity. These sets are in 
wire form, 0.5 mm in diameter, and 5 cm. long, with colored coatings 
to identify the individual chemical composition. 

The compositions of the alloy were chosen especially for direct 
calibration of the electron-probe microanalyzer for the gold-silver 
and gold-copper systems and for the testing of theories of correction 
calculations for electron-probe microanalysis. Because of the high 
homogeneity and well-determined composition, the standards will 
also be useful for other methods of microanalysis, including laser- 
probe and optical emission spectrometry, and spark-source mass 
spectrometry. 

Standard reference materials for micro analytical methods have 
well-determind composition, and must be homogeneous on the micro- 
scopic level on which the analysis is performed. These sets of SRM's 
now offered by NBS is the result of a two-year program, including 
investigation of the compositions needed for the standards, their care- 
ful preparation, and their characterization. The materials were pre- 
pared from highest-purity gold, silver, and copper and the alloys were 
heat-treated at NBS to obtain maximum homogeneity. 

Precautions were taken to minimize contamination. The alloy stand- 
ards, in the form of wires, were heat-treated at NBS to improve micro- 
homogeneity. The pure metal standards were examined by the resid- 
ual resistance ratio technique and the total of active impurities in each 
was estimated to be about 0.001 percent, The final standards were 

103 



examined spectrographically for metallic impurities; no significant 
impurities were found at detection limits ranging from 0.0001 to 
0.010 percent. 

Variation in composition along the full length of each alloy wire 
was investigated by electron probe microanalysis, using a specially 
designed automatic data collection system for areas 25 ^m in diam- 
eter at the two ends and at two evenly spaced intermediate positions. 
The observed differences in composition for the four positions, ex- 
pressed as the range between the highest and lowest values for each 
alloy, were close to the repeatability of the method. 

Homogeneity along the wires was also tested by measurement of the 
residual resistance ratio. These measurements indicated that the (mac- 
roscopic) variation of composition along all standard wires did not 
exceed 0.2 percent. 

Variation in composition with the cross section of the wires at the 
four positions along the wire was also investigated by electron probe 
microanalysis. For each cross section, measurements were made along 
two diagonals at right angles. On each diagonal, determinations were 
made at 25 points, 1 /mi or less in diameter, starting and ending at 
approximately 25 /un from the edge. For each alloy, the element 
which could be determined with the better precision was used in 
the evaluation. The variations was calculated in terms of the standard 
deviation for an individual determination for each traverse. 

The homogeneity on a microscopic scale was further investigated 
by performing quantitative measurements in two-dimensional assays 
of 10 X 10 points on each of the four cross sections. The distance be- 
tween adjacent points was 3.5 /mi. This was repeated for three of 
the cross sections so that 6 to 8 arrays were obtained on each alloy. 

Isotonic Standards and Neutron-Density Monitor: SRM 951, 
SRM 952, SRM 953— Two new boron isotopic SM's-a normal boron 
and a boron-10 standard — were prepared. The first is a boric acid 
of high purity and homogeneity for use in calibrating equipment and 
measuring the cross section of the boron (n,a) -Lithium [B(7i,«)Li] 
reaction. This cross section, particularly at thermal neutron energy 
(corresponding to a velocity of 2200 m/s) is one of the most important 
standard neutron cross sections used to calibrate equipment that 
measures neutron flux density. 

The new boron isotopic standard was prepared from a lot of boric 
acid that is uniform in isotopic composition and that adjusts to a 
stoichiometric composition after about 30 minutes exposure to normal 
room humidity (approximately 35-percent relative humidity). 

The boric acid has an acidimetric assay of 100.00±0.02 weight per- 
cent and an absolute abundance ratio of 10 B/ 11 B = 0.2473±0.0002. 

The assay was performed by coulometric titration of samples vary- 
ing in size from 0.2 to 1.0 g of boric acid, dissolved in 100 ml of a 

104 



preneutralized solution of 1 M in KC1 and 0.75 M in mannitol. The 
inflection-point of the potentiometric curve obtained from measure- 
ments with a glass-calomel electrode system was taken as the end- 
point. The pH of the maximum inflection-point will vary from 
approximately 7.9 to 8.5 for the range of samples sizes given above. 
The titration was conducted in the absence of carbon dioxide. The 
indicated tolerance is at least as large as the 95 -percent confidence 
level for a single determination of any sample in the lot of material. 

The average essentially indicates a boron-hydrogen ion ratio of 
1.0000, as separate examination shows the material contains less than 
0.001 percent of free strong acid. 

The abundance ratio was determined by single filament solid- 
sample mass spectrometry, using the ion Na 2 B0 2 + . Mixtures of known 
10 B/ X1 B ratio (at a 1 : 4, 1 : 1, and 4 : 1 ratio) were prepared from high- 
purity separated isotope solutions and were used as comparison stand- 
ards. A correction was made for the 16 0/ 17 ("B/^B ratio - 0.00079) . 
The limits of error are based on 95-percent confidence limits for the 
means of the ratio measurements and on allowances for the known 
sources of possible systematic error. 

The second SRM, a 95-percent boron-10 boric acid, was issued to 
supplement the normal boric acid and provides materials for the cali- 
bration of mass spectrometers at the 95-percent boron-10 level. 

The boric acid has an absolute abundance ratio of 10 B/ 1:L B of 18.80, 
and an acidimetric assay of 99.97 percent. The material is useful as a 
"spiking" material for the determination of boron by isotopic dilu- 
tion, as well as for the calibration of mass spectrometers. 

Many of the power reactors contain control systems involving boron, 
so the material should be particularly useful in the nuclear power 
field as well as in the determination of "trace element levels" in the 
ferrous metals and agricultural fields. 

A description of the various methods used in the characterization of 
the normal and boron-10 enriched boric acid SRM's is published in 
full detail and available in NBS Miscellaneous Publication 260-17. 

A new SRM, a cobalt in aluminum alloy, for the measurement and 
standardization of neutron densities was certified. 

The accurate determination of thermal neutron densities is essential 
in irradiation tests in obtaining a basis for comparison of neutron den- 
sities among reactors, in applying data in the design of reactors, and in 
understanding the mechanisms of radiation damage. Cobalt alloys, 
particularly 0.1 wt percent cobalt in aluminum, have been widely used 
to measure thermal neutron densities in almost all irradiation experi- 
ments on materials. Of increasingly major importance, however, lias 
been the need for a material of the highest possible homogeneity for 
which an accurate determination of the cobalt content is provided. 

This SRM also will prove useful to the activation analyst for map- 

105 



ping relative variations in neutron densities along the length and 
width of irradiation containers, for determining the integrated neutron 
flux density (insofar as small lengths approximate a sphere), and for 
determining long-term variations of the neutron density at given ir- 
radiation positions. For most applications, these measurements will be 
made on a relative rather than an absolute basis. 

The neutron-Density Monitor Wire was designed to meet these 
needs. It is a cobalt in aluminum wire 0.5 mm in diameter, which was 
prepared using specially selected high-purity starting materials. Based 
on results obtained at NBS by activation analysis and spectrophoto- 
metric analysis, the cobalt content is certified at 0.116 wt percent. 

Extensive homogeneity testing of the wire was performed by a 
variety of methods at the NBS laboratories in Gaithersburg, Mary- 
land, and Boulder, Colorado. The wire material selected for certifica- 
tion was found to be homogeneous for sample lengths of 1 mm or 
longer. 

Acrylonitrtte — -Butadiene Rubber Standard: SRM 391 — For many 
yeiars the Office of Standard Reference Materials has made available 
to the rubber industry rubbers and other materials for rubber-com- 
pounding. The SRM's currently supplied are natural rubber (NR), 
two types of styrene-butadiene rubber (SBR ) , and butyl rubber (IIR) . 
A new rubber is now added to this group, namely, acrylonitrile-buta- 
diene rubber (NBR). 

This rubber is intended for use in the standardization of testing 
among laboratories and as a reference rubber in quality control and 
testing for resistance to deterioration by oil, gasoline, and other hydro- 
carbon products. 

The NBR used for the new SRM contains approximately 33 per- 
cent combined acrylonitrile. The rubber is wrapped in polyethylene 
film, and packaged in multiwall paper bags containing 25 kgs. The 
uniformity of the lot was established by tests on samples taken after 
each tenth package during manufacture. 

The Mooney viscosity of this rubber was determined to be 49.0d=1.0 
ML 1 + 4 (100 °C), using a modification of ASTM Designation 
D1646-68. 

Compounds for evaluation were prepared in accordance with the 
formulation and mixing procedure described in ASTM Designation 
D15-66T for Standard Formula IF using NBS Standard Reference 
Compounding Ingredients. The viscometer cure characteristics of each 
compound were determined at 150 °C according to ASTM Designa- 
tion D1646-68. The minimum visvosity, incipient cure time, and cure 
index (the time required to increase from 5 to 35 points above the 
minimum) were measured. 

The remainder of the compounds were vulcanized according to 
ASTM Designation D15-66T and measurements were made on these 

106 



vulcanizates for stress at 300-percent elongation, stress at failure, and 
elongation at failure (ASTM D412-68), strain under a stress of 400 
pounds per square inch (2.75 meganewton per square meter) (ASTM 
D1456-61), and electrical resistivity [Ind. Eng. Cliem. 44, 159 
(1952)]. 

This new acrylonitrile-butadiene rubber standard complements the 
other rubber and rubber-compounding SRM's available from the NBS 
Office of Standard Reference Materials. 

Deuterated Hydrocarbons Standards: SRM 2175, SRM 2176— -The 
Bureau announced the availability of two new deuterated hydro- 
carbon SRM's, ethand-<# 6 and propane-l,l,l-r/ 3 . They are certified as 
chemical standards and are intended primarily to aid research work 
ers in the analysis of deuterated or partially deuterated hydrocarbons. 

In kinetic studies (pyrolysis, photolysis, radiolysis, etc.) in which 
deuterium labeling of reactants is used, partially deuterated molecules 
are formed as products. In order to specify the isotopic structure of 
these molecules, comparison mass spectrometric cracking patterns are 
determined in the same instrument in which the actual analysis of 
the product is made, since each commercial instrument shows a differ- 
ent behavior. It is for the determination of these comparative crack- 
ing patterns that these SRM's are intended. 

The deuterated hydrocarbons were prepared by the photolysis of 
ketones and purified by a combination of gas chromatography, 
absorption, and distillation. Chemical purity was determined by gas 
chromatography and isotopic purity by mass spectrometry, and con- 
sideration of reactions entered into by the reagents. 

The ethane-^, ; has a chemical purity of greater than 99.9 mole per- 
cent; the only detectable impurity being a trace of propane. Its iso- 
topic purity is 99.8 ±0.05 atom percent deuterium combined as 98.9 
mole percent C 2 D 6 and 1.1 mole percent C 2 H 5 D. 

The propane-1, 1,1-^a has a chemical purity of greater than 99.9 mole 
percent; the detectable impurities identified as approximately 0.03 
mole percent ethane and 0.01 mole percent ethylene. Its isotopic purity 
is 99.4 mole percent OD 3 CH 2 CH 3 and 0.6 mole percent CD 2 HCH 2 CH 3 . 

Cyclohexane Dielectric Constant Standard SRM 1511 — NBS issued 
Cyclohexane as the first of three liquids to be certified by the Office 
of Standard Reference Materials for dielectric constant standards. 
The dielectric constant of this material was measured at 20, 25, and 
30 °C and it is felt that calculated values can be used from 10 to 40 °C 
without introducing appreciable errors. This SRM is useful for the 
determination of the geometric capacitance of two terminal dielectric 
constant cells and for checking the linearity of the geometric capaci- 
tance of the three-terminal, or absolute, cells. 

The dielectric constant of most materials is commonly defined and 
measured as the ratio of the capacitance of a capacitor immersed in 



375-572—70- 



107 



the medium in question to that in vacuum. Because most test capacitors 
(cells) are nonideal, for accurate work they must be calibrated using 
air and one or more materials of known dielectric constant. 

Reference Materials for Thermochemistry : SRM 72 J^ — Determina- 
tions of the heats of solution of a standard reference material, tris 
(hydroxymethyl) amino methane (TEIS) were carried out in a 
highly precise adiabatic solution calorimeter and used for prepara- 
tion of a certificate of the heating value. This reference material 
(Standard Sample No. 724) is very much needed by scientific workers 
in the thermochemistry of solution processes, in order to detect and 
eliminate sources of systematic error. Such systematic errors have 
caused numerous discrepancies among measurements made in dif- 
ferent laboratories. The precision of the recent measurements is 
somewhat better than 0.05 percent, and illustrates the quality of the 
measurements that can be made with this recently developed calorim- 
eter. Both the heat of reaction with dilute IIC1 (AIT negative) and 
with dilute NaOH (AH positive) have been determined, thus pro- 
viding comparison reactions for both endothermic and exothermic 
reactions. 

New Chemical M icro standard : SRM 1800 — Problems encountered 
in the calibration of sensitive chemical analytical instrumentation 
have been resolved by a recent IMR discovery that individual ion- 
exchange beads can be used to hold extremely small and accurately 
known amounts of matter. Techniques have been developed for pre- 
paring beads containing from one nanogram (10~ 9 g) to less than a 
billion atoms. The preparative methods include the use of "clean" 
conditions for loading and isolating the beads. The first microstandard 



: * 










,#*,:# 



Standard reference materials being prepared by the dispersal of chemically 
loaded ion-exchange beads on glass slides in a clean room. 



108 



has now been made available to the public. It consists of calcium ions 
loaded onto cation exchange beads in amounts ranging from 10" 9 to 
10 -11 g. The material is designated Standard Reference Material No. 
1800. Microstandards for a series of other elements are in preparation. 
Oceanographic Conductivity Standards — The electrical conductiv- 
ity of sea water provides the most precise and convenient measure of 
salinity available to the oceanographer. For the reliable identifica- 
tion of water masses and for the calculation of related properties 
such as density and sound velocity, measurements of conductivity are 
needed with a precision comparable with that of the best research 
measurements on electrolyte solutions. A series of sodium chloride 
solutions of certified conductivity has been prepared for use in cali- 
brating oceanographic salinometers. The solutions have temperature 
coefficients of conductivity sufficiently close to those of sea water to 
have practical utility, and yet they are more readily prepared and 
characterized in terms of concentration and purity than either natural 
or synthetic sea water. With conductivities known to 0.01 percent, 
these reference standards are expected to find wide application in 
oceanographic work. 

DATA ON THE PROPERTIES OF MATERIALS 

This program stresses the precise measurement of materials prop- 
erties and the development of new and improved measurement tech- 
niques. It embodies experimental and theoretical investigations of 
chemical and physical phenomena of importance to science and in- 
dustry, and seeks to correlate chemical and physical properties of 
materials with their composition and structure. 

Atomic and Molecular Data 

Infrared and Ultraviolet Spectroscopic Studies of Reactive Mole- 
cules Isolated in Inert Solid Matrices — Using matrix-isolation tech- 
niques, the stretching fundamentals of SiCL and SiCl 3 and all of the 
vibrational fundamentals of SiF 2 and SiF 3 have been observed. This 
permitted an estimate of the approximate structure of these species. 

In ultraviolet studies of the reaction of photolytically produced H 
or D atoms with CO at cryogenic temperatures, the absorption counter- 
part of the hydrocarbon flame bands has been observed for the first 
time. The attribution of this band system to HCO has been confirmed. 
Both the CO-stretching and the HCO-bending vibrations have been 
found to be appreciably excited in this transition. The observation of 
the ground-state vibrational fundamentals of HCO in infrared spec- 
troscopic studies made possible a detailed assignment of the hydro- 
carbon flame bands. 

109 



A furnace was developed for studies of the reaction of gases with 
high-temperature metal surfaces. Several of the first-series transition- 
metal (Cr, Mn, Fe, Co, Ni) dichlorides have been trapped in inert 
so] id matrices in sufficient concentration for direct observation of their 
stretching fundamentals under conditions such that interactions with 
neighboring dichloride molecules are virtually completely eliminated. 
Two previously unreported electronic transitions have been observed 
between 500 and 440 mn for NiCl 2 , one of them with extensive vi- 
brational structure. 

Photolysis of matrix-trapped alkali metal atoms has provided a 
source of electrons in the matrix. These were used to interact with 
ground state C 2 species in an argon matrix to give C 2 . A reassignment 
of the adsorptions previously ascribed to the Swann transition 
resulted. In a similar manner the species NO2 has been stabilized in 
sufficient concentration for the driect observation of one vibrational 
fundamental. 

Magnetic Resonance of Copper in Entile — -The magnetic resonance 
spectrum of divalent copper ions in titanium dioxide (rutile) was 
examined in detail. Information was gained about both isotopes of 
copper and the interactions of the ion with the host crystal. The ex- 
periments determined the electronic ^-factors, magnetic hyperfine 
coefficients, and the electric quadrupole coupling parameters. The 
magnitudes of the quantities were obtained experimentally and the 
absolute signs predicted theoretically from a model which gives a 
consistent picture of the ordering of the electronic states of the copper 
ion. The theory includes the effects of the orthorhombic crystal field 
and covalent sharing of the valence electrons of the copper. 

Development of a Highly Stable Pulsed NMR Spectrometer — Scien- 
tists in IME have recently developed an extremely stable pulsed NMR 
spectrometer which has made it possible to perform meaningful Carr- 
Purcell experiments. Such experiments are used to measure dynamic 
processes in molecular systems. The spectrometer is currently being- 
used in a joint program by NBS and NIH scientists to study hindered 
rotation in cytosine derivatives. Cytosine is one of the molecular build- 
ing blocks of DNA and RNA. 

Determination of 13 C Relaxation Mechanisms — In a joint research 
program, I MR scientists and scientists at the Division of Computer 
Research and Technology and the National Institute for Arthritis 
and Metabolic Diseases (both at NIH) have for the first time made 
a quantitative determination of the contribution which various relax- 
ation mechanisms (such as direct dipole-dipole, chemical shift 
anisotropy, spin-rotation, etc.), make to the total 13 C spin-lattice relax- 
ation time. Such information has great importance for planning ex- 
periments on the $200,000 super-conducting NMR spectrometer 
scheduled for delivery to NIH in the autumn of 1969. Also, such in- 

110 



formation is of importance in checking the fundamental theories of 
magnetic interactions in molecular systems. 

Electronic Structure of P-F Bonds in Fluor ophosphates — Using 
x-ray diffraction and NMR spectroscopy, IMR, in cooperation with 
University of Illinois scientists, has made it possible for the first time 
to determine the sign and the magnitude of the anisotropics of both 
of the chemical shift tensors (one for 19 F and one for 31 P) and the 
31 P- 19 F spin-coupling tensor in the PFO = 3 anion. Such a determina- 
tion requires a precise knowledge of the crystal structure of the fiuoro- 
phosphate and a detailed line shape analysis of the 31 P and 19 F NMR 
line shapes for spectra obtained at — 190 °C. The knowledge of the sign 
and magnitude of the 31 P- 19 F spin coupling anisotropy has resulted 
in the first and only unequivocal experimental determination of the 
absolute sign of an NMR spin-coupling constant. This information 
is of great value both to synthetic chemists and to theoreticians 

Relaxation Process of Chromium Ion in Potassium Alum — The elec- 
tron spin relaxation process of potassium chrome alum and potas- 
sium chrome aluminum alum was investigated by measuring the change 
in the static d-c magnetization as a function of the cw microwave power 
absorbed at electron resonance, and also by observing the transient 
recovery of the microwave resonance signal. At liquid helium tem- 
peratures the direct spin-lattice relaxation process is the dominant 
rate-determining process for magnetically dilute potassium chrome 
aluminum alum, but for the magnetically concentrated crystals the 
spin-lattice process can easily be obscured by the lattice-bath relaxation 
process. There is some evidence that the lattice-bath relaxation rate is 
determined by the thermal conductivity of the helium exchange me- 
dium. Within the experimental error the spin-lattice relaxation meas- 
urements at 14.5 GHz and those of other workers at 9 GHz are in agree- 
ment with the calculations made by Van Vleck in 1940. His theory 
predicts that for the direct process at high fields t x TH 2 is constant 
where T is the temperature, r a is the direct spin-lattice relaxation time, 
and II the magnetic field. The experimental values of n agree with the 
calculated to about a factor of five and the exponential of II is approxi- 
mately two. The theory also predicts that, to first order, Tl is isotropic 
and independent of the chromium ion concentration, and this also ap- 
pears to be borne out experimentally. 

Solid State Data 

Versatile Probe for Optical-EPR Studies — A sample EPR probe, 
developed in IMR, can hold any sample material for experimental in- 
vestigation under varying conditions of illumination, temperature (as 
low as 1.3 K), and microwave frequencies. The versatility of the new 
probe will aid scientists in improving the quality of lasers, in studying 
the photochromic properties of crystals, and in investigating the solid 

111 



state properties of crystals for prospective use in display panels and 
as holograms for storage purposes. 

The probe is a pipelike device that can hold any crystalline or pow- 
dered material to be investigated. One of the probe ? s outstanding fea- 
tures is a rigid but adjustable coaxial coupling system (coaxial line) 
that physically and electrically connects the resonance "test" cavity 
at the lower end of the line to the microwave system at the upper end, 
with minimum energy losses and stray reflections. In addition to the 
coaxial line, the probe consists of a microwave source, a microwave 
transition coupling system, a light pipe, an iris assembly, and a reso- 
nance cavity. 

The probe has been tested with considerable success in experiments 
on a double-doped ZnS : Cu, Ga crystal. NBS data on the photon ab- 
sorption lines of the crystal at various magnetic field strengths and 
microwave frequencies showed good agreement with results obtained on 
the same crystal by other scientists. 

Subsequently this probe was used to study photosensitive color cen- 
ters in a single crystal of calcium oxide. An EPR width of 10" 6 tesla 
w r as obtained, the narrowest line width ever observed in solid samples. 




Optical-microwave probe showing the microwave transition coupling system, 
light pipe, iris assembly, and resonance cavity. The probe holds sample mate- 
rials during EPR studies. 



112 



The increase in the production of color centers responding to excited 
light, and the color centers' decay after the removal of the excited light, 
could be traced by the EPR signal monitor. 

Proposed Standard Reference Material for Mossbauer Spectros- 
copy — A new standard material for use in Mossbauer spectroscopy has 
been proposed as a result of nuclear magnetic resonance experiments 
recently performed by IMR scientists. The intermetallic compound, 
TiFe, possesses many advantages as a material with which to cali- 
brate the applied magnetic field, H, in 57 Fe Mossbauer experiments. 
The Fe possesses a cubic symmetry, avoiding complications of quacl- 
rupole effects. The Knight shift has now been measured with good 
precision by nuclear magnetic resonance. A further advantage is that 
the Knight shift is nearly temperature-independent. Measurements of 
internal fields at the 57 Fe nucleus should be more precise using this new 
standard. 

Luminescence in Semiconductors — The use of photoluminescence 
and photoconductivity in the elucidation of dynamical processes was 
applied to insulating strontium titanate and thallous bromide. Stron- 
tium titanate was found to exhibit a sharp emission line at 800 nm, 
with 31 satellite lines arising from phonon cooperation (vibrational 
sidebands). Excitation spectra show that the center responsible for 
the photoemission is not directly excited by resonant-energy transfer 
in which the excitation of electrons and holes is transferred to the ex- 
citing center by a radiationless transfer of energy. Then the excited 
center decays, emitting photons and phonons. 

Another process, known as Auger recombination, has been observed 
in TIBr on excitons trapped at impurities. In this process the impurity 
exciton is deexcited by a spontaneous transfer of charge to the conduc- 
tion band where it dissipates energy. The remaining energy at the 
center is dissipated by photon and phonon emission. 

Temperature dnd Pressure Dependence of Dielectric Constant of 
Cadmiwrn Fluoride — Although cadmium fluoride has a large insulator- 
like energy gap of 6.0 eV, doping transforms it into a well-conducting 
semiconductor. The static dielectric constant at room temperature and 
pressure was determined to be 8.33 and has a positive temperature 
dependence coefficient, thus agreeing with reported theories predicting 
a positive coefficient for compounds with a dielectric constant of less 
than 10. Pressure dependence along with the temperature dependence 
of the dielectric constant were combined with compressibility and 
thermal-expansion coefficient to complete the picture and give informa- 
tion on the temperature dependence of the polarizability, as well. A 
value of 0.80 at room temperature for the Szigeti charge was 
calculated. 

Propagation of Acoustic Phonons in Iieisenberg Paramagnets — 
The propagation of sound waves in ferromagnetic and anti-ferromag- 

113 



netic insulators has been studied within the framework of two models 
which describe the interaction between the spin system and the lattice. 
Expressions for the frequency shifts (phonon renormalizations) at 
high temperatures and near the transition temperature are obtained 
now in terms of time-dependent correlation functions. The frequency 
shifts for long-wavelength phonons are negative, increase rapidly in 
the vicinity of the transition temperature, and are less singular than 
the attenuation coefficients. The ratio of the frequency shift to the un- 
perturbed phonon frequency is independent of the phonon frequency 
for long wavelengths. These results agree qualitatively with present 
experiments. 

Development of Low-Threshold Laser Glasses — In a cooperative 
project with the Night Vision Laboratory, U.S. Army Material Com- 
mand, experimental glasses doped with various rare-earth and transi- 
tion metal atoms have been made in order to evaluate their fluorescent 
properties. Radiative and nonradiative energy transfer and decay 
processes have been investigated in silicate glasses codoped with Eu 
and Ncl. Energy transfer from Eu to Nd was established from an 
examination of the excitation spectra and the increased Eu decay rates 
in the presence of Nd. Measurements of the concentration dependences 
of the Eu +3 and Nd +3 fluorescence lifetimes reveal the presence of four 
distinct processes arising from various ion-ion interactions: (1) self- 
quenching of the Nd +3 fluorescence, (2) self -quenching of the Eu +3 
fluorescence, (3) nonradiative energy transfer from Eu +3 to Nd +3 , 
and (4) Eu quenching of the Nd +3 fluorescence. This last process 
decreases the radiative quantum efficiency of the 4 F 3 / 2 state of Nd +3 , 
thus limiting the attractivness of Eu sensitization for Nd laser action. 

Polarizable Ion Models for the F Center in Ionic Crystals — The 
states of the F center have been considered on the basis of models which 
treat the movement of the nearest neighbors to the F center and the 
F electron in a self-consistent manner. The lattice is first described in 
terms of a classical ionic-crystal theory. The theory has been extended 
now to treat the nearest neighbor ions in a quantum mechanical man- 
ner. The one-defect electron (the F electron) is treated according to 
polarizable ion models. The absorption energy, the emission energy, the 
lifetime of the first excited state, the zero-phonon transition energies, 
and the Huang-Rhys factors are evaluated for two models which differ 
in the rigor used to compute the polarization of the nearest and next 
nearest neighbors. The model which contains the more rigorous evalua- 
tion of the polarization agrees best with the experimental results for 
CaO and MgO. 

Thermodynamics and Transport Data 

Chemical Thermodynamics Data Center — During the past year the 
Chemical Thermodynamics Data Center completed and published Part 

114 



4 of the Series, TN 270, "Selected Values of Chemical Thermodynamic 
Properties." This volume contains values for the room-temperature 
properties (heats and Gibbs energies of formation, entropy, enthalpy, 
and heat capacity) for compounds of 19 elements. This is part of the 
continuing NBS program on the maintenance of tables of self-con- 
sistent data in thermodynamics, and has now covered approximately 
one-half of the elements in the Periodic Table. 

The Data Center has also completed a comprehensive Bibliography 
and Substance-Property Index of the published literature for 1968 
with respect to thermodynamic measurements on inorganic compounds. 
It contains over 8,000 index entries obtained from nearly 2,800 pub- 
lished articles and will appear in the 12th Edition of the Bulletin of 
Thermodynamics and Thermochemistry, sponsored by the Commis- 
sion on Thermodynamics of the International Union of Pure and 
Applied Chemistry. 

Ionization and Appearance Potential Compilation — A comprehen- 
sive compilation has been prepared and published, covering ionization 
potentials, appearance potentials, and heats of formation of gaseous 
positive ions. These quantities are based on measurements employing 
techniques of mass spectrometry, photoionization, photoelectron spec- 
troscopy, untraviolet spectroscopy and, in some instances, on semi- 
empirical molecular orbital theory. The compilation covers the period 
1955-1966, including information on more than 1,500 ionic species 
and giving more than 700 references to work in this field. This infor- 
mation is of fundamental interest in all areas of gaseous ionization 
phenomena. 

Dissociation Energies of Fluorine and Hydrogen Fluoride — Deter- 
mination of the dissociation energy of the F 2 molecule has been a 
difficult experimental problem. Many determinations of this quantity 
have been attempted, representing a number of different experimental 
techniques, and resulting in a wide range of proposed values. In 
a new approach to this problem, thresholds unambigously assigned 
to dissociative ionization and ion-pair formation were meas- 
ured with a photoionization mass spectrometer for the related 
molecules F 2 and HF. Although the resulting dissociation ener- 
gies for both molecules are significantly smaller than previously 
favored values, these new data are supported by their consistency with 
the accepted heat of formation of HF. These measurements will affect 
the calculation of binding energies of fluorine-containing molecules. 
The new results have already stimulated a reinvestigation of the emis- 
sion spectrum of the HF molecule. 

Critical Phenomena in Binary Liquid Mixtures * — To study critical 
phenomena in binary liquid mixtures, the system 3-methylpentane- 



* In cooperation with the Institute for Basic Standards. 

115 



nitroethane was selected at NBS. The refractive index of the liquid 
components of this system is such as to minimize multiple scattering 
in studying critical opalescence. Experiments were carried out to 
determine the intensity of scattered light, the curve of coexisting con- 
centrations, and the behavior of the surface tension as a function of 
temperature. Stimulated by the work at NBS, several research groups 
elsewhere have initiated experimental studies to investigate other 
properties for the same system. 

Deuterium Isotope Effect on the Ionization of Weak Acids — It has 
long been known that acids weak in water are still weaker when dis- 
soved in deuterium oxide. The difference in strength, expressed as 
hpK (where K is the ionization constant), varies with the acidic 
strength (pK) in water in a manner thought my many to be linear. 
The straightline variation has been difficult to confirm, because of a 
lack of precise data for the pK of a moderately strong acid such as 
phosphoric acid or sulfuric acid. Such data are notoriously difficult 
to obtain. The ionization constant of phosphoric acid, however, was 
carefully measured at NBS 18 years ago and has now been determined, 
using identical techniques, in deuterium oxide over a temperature 
range of 5 to 50 °C. The values of f\pK thus obtained thoroughly 
confirmed the linear variation, but a critical examination of the best 
data for a variety of acids revealed that only inorganic acids appear to 
fall uniformly on a straight line at low values of pK. Many moder- 
ately strong organic acids, on the contrary, show considerable devia- 
tions. It is concluded that the deuterium isotope effect is not as simple 
as has often been assumed. 

pH Standard for Clinical Use — Changes in the acid-base balance of 
blood and other biologic fluids are a useful indicator of pathological 
conditions in the human body. For the most part, the region of critical 
interest lies between pH 6 and pH 8. Accurate pH measurement and 
control has been hampered by the lack of buffer materials capable of 
fixing pH in this physiologically important range of acidities. A new 
buffer substance called u bis-tris" (the chemical name is 2,2-fo\s'[hydrox- 
ymethyl]-2,2'2''-nitrilotriethanol) has recently been found suitable 
for pH measurement and control between pH 5.5 and 7.5. Further- 
more, solutions of this substance are compatible with most biologic 
fluids. To make this buffer material most useful to clinical chemists, 
the acidic dissociation of "bis-tris" has been accurately determined 
from to 50° C by careful electromotive- force measurements. In 
addition, the pH values of several concentrations of u his-tris" buffers 
were determined. As a result of this work, it is now possible to control 
pH accurately in biomedical studies performed in the mildly acidic 
range and to standardize pH equipment at a pH near 6.5. 

Standards for I on- Selective Electrodes — The rapid increase in the 
types of ion-selective electrodes made available during the past two 

116 



years has brought a widespread expansion in the applications of these 
new sensors. New uses have stimulated the demand for standards of ion 
activity, the property most directly related to the response of these 
electrodes. A numerical scale of individual ion activities, consistent 
with the conventional scale on which the measurement of pH is based, 
has now been proposed by NBS, and the certification of activity stand- 
ards for sodium and chloride ions is under way. The performance of 
electrodes for the determination of calcium and fluoride was evaluated 
by a procedure that has been adopted for the examination of each new 
type of sensor. The response is first compared with that predicted by 
theoretical equation as concentration and temperature are changed. 
The consistency of the response with the conventional scale of activity 
is evaluated, and the magnitude of liquid- junction errors in the meas- 
urement of ion activity is estimated. Priorities are established through 
consultation with the instrument manufacturers and users of the 
electrodes. 

Melting Point of Aluminum Oxide — A task force on secondary 
temperature standards, chaired by an NBS staff member and sponsored 
by the Commission on High Temperatures and Refractories, Inter- 
national Union of Pure and Applied Chemistry, has completed a co- 
operative determination of the melting point of aluminum oxide 
(A1 2 3 ). In all, nine scientific groups representing seven countries 
participated in the joint experimental effort. All work was performed 
utilizing a common supply of high-purity A1 2 3 . Experimental tech- 
niques varied, depending upon the individual investigator. The value 
for the alumina point, as recommended by the task force, is 2053° with 
a standard deviation of ±4° C (IPTS 1968). 

In addition to actively supporting the task force, NBS is now de- 
veloping an A1 2 3 standard reference material. The high-priority 
standard sample, in 10 g lots, will have a certified melting point with 
an overall uncertainty of less than ±5° C. The SRM will be par- 
ticularly useful in the fields of high-temperature chemistry and re- 
fractories for in situ temperature-calibration purposes. 

Heat Capacity Adjustments for Natural Rubber Confirmed — Recent 
precise measurements have confirmed NBS proposals for adjustments 
required in previously determined values of the heat capacity of 
natural rubber (<??Vl,4-polyisoprene) near room temperature. Accurate 
knowledge of this thermophysical property is essential to efficient 
commercial manufacturing and processing operations in the auto- 
mobile-tire and other rubber industries. The original values were 
determined in pioneering work at NBS in 1935. These values satisfied 
technological needs for several decades. However, refined industrial 
operations resulting from technological progress eventually suggested 
that these original values were not sufficiently accurate for thermo- 
physical calculations required in the more advanced technological 

117 



processes. On the basis of new knowledge gained from basic research 
on polymer crystallization during the intervening decades, NBS 
scientists concluded that the original measurements had been adversely 
affected by undetected crystallization processes which were unknown at 
the time those measurements were made. By taking this new knowledge 
into account, predictions were made for adjustments which needed to 
be applied to the 1935 values in order to obtain values sufficiently ac- 
curate to satisfy today's technological requirements. New heat-capacity 
measurements have now been made on synthetic (rather than natural) 
m-l,4-polyisoprene in an adiabatic calorimeter which covers the tem- 
perature range from 2 to 360 K with a precision of better than 0.1 
percent of the values. The synthetic polymer is the result of industrial 
research advances in the past decade and is considered to be tech- 
nologically equivalent to the natural product, over which it has valu- 
able economic advantages. These new measurements confirm the pro- 
posed adjustments, and the basis for the thermophysical calculations 
required in the rubber industry is again re-established on the basis 
of firm measurements. 

D iff its ion in Alloys — Kinetic equations have been developed describ- 
ing diffusion in a random multicomponent alloy. It has been found that 
simple relations between the atom and vacancy diffusion parameters 
can be calculated if the atoms and vacancies in the crystal are as- 
sumed to be randomly distributed and suitable averages are taken. 
These relations, which should apply well to many nondilute alloys, 
predict a forbidden region in the plot of diffusion coefficient ratios 
versus composition, and indicate a possible kinetic source of negative 
diffusion coefficients. 

Chemical Kinetics 

Theory of Chemical Kinetics — Resonant scattering theory, orig- 
inally developed for atom-electron interactions, has been applied by 
IMR scientists to the description of chemically interesting collisions. 
The result is a complete quantum mechanical description of the inter- 
action between molecules in decomposition and combination reactions. 
Taken together with recent advances in the calculation of potential 
energy surfaces, this theory provides the basis for exact calculation 
of rates of chemical reactions. 

High-Pressure Photoionization Mass Spectrometry — A unique 
photoionization mass spectrometer has been constructed by IMR sci- 
entists for investigation of ion-molecule reactions occurring at elevated 
pressures in the vapor phase. This instrument has been successfully 
used to derive accurate rate constants and cross sections for the reaction 
of thermal organic and inorganic ions in the pressure range 0-10 torr. 
Using selectively labeled deuterium-containing analogs, the stereo- 
specificity of many of these processes has also been determined. 

118 




m&i&y 




The kinetics and mechanisms of chemical reactions initiated by high energy radia- 
tion being studied with a rare-gas resonance lamp. 

Photoionization in the Far Ultraviolet — In recent years consider- 
able information has been accumulated concerning the kinetics and 
mechanisms of chemical reactions initiated by high-energy radiation, 
especially in the lower-molecular- weight hydrocarbons. Earlier work 
has demonstrated the feasibility of using photolysis techniques with 
high-energy photon sources as a means of studying the unimolecular 
decomposition of parent ions and superexcited molecules as well as 
the subsequent reactions of the fragment ions or radicals produced by 
such dissociations. Numerous investigations of this type have been 
carried out using krypton (1236 A, 10.0 eV) and argon resonance 
lamps (1067-1048 A, 11.6-11.8 eV). In order to extend such studies to 
still higher energies, self-contained helium (581 A, 21.2 eV) and neon 
resonance lamps (744-736 A, 16.7-16.8 eV) have now been designed, 
constructed and used successfully in such experiments. 

These helium and neon resonance lamps which have a high spectral 
purity, a high intensity, and a long lifetime have recently been used 
in several photoionization studies. The results have been compared 
with the results from the gamma-ray radiolysis of the same hydro- 
carbons. These same resonance lamps have been used to derive ac- 
curate extinction coefficients and ionization quantum yields for a large 
number of organic and inorganic compounds. 

Decomposition of Hydrocarbons — Hydrocarbon molecules decom- 
pose at high temperatures by splitting into two free radicals by scission 



119 



of carbon-carbon bond. A systematic study of the rates of these decom- 
position reactions has been made using the single pulse shock tube 
technique. It shows that the rates and mechanisms are predictably 
dependent upon variations in molecular structure. As a result, a large 
number of decomposition rates may be predicted from a limited set of 
measurements. For example, from 9 measured decomposition rates 27 
other rates have been predicted. Where cross-checks are available, the 
agreement is good. 

Vacuum Ultraviolet Flash Photolysis — The vacuum ultraviolet flash 
photolysis of carbon suboxide has been shown to produce carbon atoms 
in addition to carbon monoxide. Using the method of kinetic spec- 
troscopy, rate constants for the reaction of carbon atoms with hydro- 
gen, oxygen, nitrogen, nitric oxide, and methane were measured for 
the first time. Kate constants for the interaction of methylene radicals 
(produced from the vacuum ultraviolet flash photolysis of ketene and 
diazomethane) with hydrogen, nitrogen, and methane were also de- 
termined by this technique. 

Chemical Kinetics Mass Spectrometry — Reactions of atomic oxygen 
and of molecular oxygen in the lowest-lying excited state are of great 
importance in air pollution, upper atmosphere chemistry, and com- 
bustion. Rate constants for atomic oxygen reactions with about 25 







Vacuum ultraviolet flash photolysis apparatus used for the study of the chemical 

reactivity of free radicals. 



120 



alkanes and bromo- and chloralkanes have been measured at tempera- 
tures from 300 to 600 K. The first measurements have been made on 
the rates of reaction of excited molecular oxygen with organic com- 
pounds and the importance of these reactions in air pollution is under 
study. 

Surface Data 

New Technique for Surface Catalysis Studies — A novel method 
for observation of surface interactions has been developed. Two chemi- 
sorbed gases are completely separated, but contiguous — the zone of 
interaction initially is a region only a few angstroms wide. On heat- 
ing, diffusion processes can occur to widen the zone. If interdiffusion 
takes place with increasing temperature, the process is visually ob- 
servable. This new T technique appears to have interesting applications 
in studies of surface catalysis. The instrument used is the NBS- 
developed field emission microscope-molecular beam combination. A 
field-emitter tip, whose axis is perpendicular to the gas beam, is cov- 
ered with a monolayer of gas on that half of the tip exposed to the 





Field emission patterns of two separated, contiguous, chemisorbed gases (carbon 
monoxide and oxygen) on tungsten : 

1. Tungsten tip half-shadowed with oxygen (oxygen-covered portion not visible 
because of high work-function ) . 

2. Carbon monoxide condensed over oxygen on tungsten (upper portion, 
oxygen; lower portion, carbon monoxide). 

3. Pattern after heating tip to 350' K. 

4. Pattern after heating tip to 700 K for 5 minutes. 

5. Field emission pattern of clean tungsten. 



121 



beam. A second gas is similarly condensed as a second layer. Both 
depositions are done at 4.2 K. The temperature of the tip is raised to 
50 K to separate the gases by surface migration, for at this tempera- 
ture the second layer, but not the first, migrates. There results a 
monolayer over the entire tip, half of the tip covered with the first gas, 
the other half covered with the second gas. 

Chemisorption on Single-Crystal Tungsten Stir faces — Several new 
experimental methods have been developed to study the chemisorption 
of gases on single-crystal tungsten surfaces. One study of hydrogen 
desorption from a (100) tungsten disk involved using a focused lamp to 
heat the suspended crystal uniformly without introducing tempera- 
ture inhomogeneities. Two distinct binding states having desorption 
energies of about 25 kcal. mol -1 and 32 kcal. mol -1 were found. They 
are populated at room temperature in a two-to-one ratio with full 
coverage. The dipole moment per adsorbed atom was found to be 0.15 
Debye, independent of binding state. Coadsorption of hydrogen and 
deuterium resulted in isotopic mixing in both states. 

Oxygen chemisorption on a (100) tungsten was followed using + 
ion desorption stimulated by electron impact, The f3 x state from which 
+ originates occupies about y 20 of a monolayer at full oxygen cover- 
age. The ion-energy distribution curves at surface temperatures be- 
tween 300 and 1200 K provided data leading to a characteristic vi- 
brational frequency of 1270 cm -1 for the (3 X state. This and other results 
strongly imply that the j3 x state is molecularly absorbed. 

Ellipsometry — The ellipsometer is an optical instrument that meas- 
ures the properties of surfaces and thin films on the surface by the 
changes in state of polarization of light reflected from the surfaces. 
Due to its sensitivity to very thin films, for example, the ability to 
measure thickness to a few Angstrom units, it has been applied to 
studies of polymer absorption, corrosion of metal surfaces, etc. 

The errors that occur in measurements by the ellipsometer have been 
analyzed and means to eliminate them derived. The errors considered 
are an imperfect compensator in the ellipsometer, birefringence in a 
cell containing the surface, tilting of the surface, and roughness of the 
surface. A new Fortran computer program has been written to per- 
form the involved calculation required to analyze the ellipsometer 
measurements. 

Mechanical Properties 

Bulk Modules of Solid Linear Polymers — A bundle-of -chains model 
has been used to predict the bulk modulus and Gruneisen parameter 
of linear polymer crystals such as polyethylene and the n-paraffins. 
The theory uses nearest-neighbor pair potentials to calculate the sec- 
ond and third derivatives of the lattice potential energy with respect 
to volume. This model is expected to yield useful predictions of the 

122 



intermolecular thermal energy and, via the Debye equation of state, 
the thermal expansion coefficients for linear crystalline polymers. The 
predicted Gruneisen parameters were found to be considerably larger 
than for simpler molecular systems and were found to be in excellent 
agreement with results for ultarsonic and specific heat measurements 
on polyetheylene. 

Mechanical Properties of Dental Materials — A torsion pendulum 
system has been developed for determination of elastic properties and 
internal friction of dental materials. The specimen serves as the tor- 
sion bar in the system. From the frequency of the pendulum, the shear 
modulus of the specimen mateiral can be determined and from the 
damping the internal friction can be measured. A value of 3 X 10 6 
psi (2X10 9 N/m 2 ) obtained for the shear modulus of dental amalgam 
is in agreement with values obtained by ultrasonic methods. The tor- 
sion apparatus is applicable to many restorative materials and to 
natural tooth structure. Studies of the effects of temperature variations 
on the mechanical properties of dental materials and tooth structure 
will be made with this apparatus. 

Microscopic Studies of Elastic Strains in Materials — Stress-strain 
analysis in local regions of polycrystalline iron-silicon transformer 
sheet has been carried out using the divergent beam (kossel) x-ray 
diffraction method. This nondestructive measurement technique per- 
mits microscopic strain determinations near grain boundaries and 



'UK 111 ■ 




Part of the torsion pendulum system for determining elastic properties of dental 

materials. 



375-572—70- 



123 



other disturbed regions in the alloy and provides mapping the strain 
distribution. Previous mechanical and thermal treatments of the ma- 
terial determine the nature of the observed strain distribution together 
with the magnetic characteristics of the transformer sheet. 

High Cyclic Bending oj Steels — In repeated high cyclic bending, 
with constant load amplitude, the size and the shape of the plastic 
zone preceding the propagating crack is controlled by local structural 
conditions near the tip rather than by stress intensity. No significant 
correlations have been found between the experimentally determined 
sizes of plastic zone and the theoretically predicted values of Liu 
and Rice. The plastic zone sizes ahead of the propagating crack cannot 
be simply expressed as proportional to the rate of fatigue crack 
propagation, though a simple relationship exists between the rate 
and the stress-intensity factor. The relationship given by Paris, 

-prj.= QAK n , describes the rate of crack propagation only in a limited 

range of relative crack-length, #<0.5. The extent of this range de- 
pends on the structure and on the level of applied cyclic stress. 
Beyond this range, the Paris equation cannot be applied and the 
crack propagation cannot be related to the stress-intensity factor. 

Alloy Softening BOG Transition Metals — The experimental and 
theoretical basis for the unusual phenomenon of "alloy softening" has 
been clarified in three published papers. Alloy softening is the weak- 
ening of very pure metal deformed below a temperature of about 0.20 
times the melting point upon addition of dilute concentrations of 
solute. Softening in interstitial alloys is attributed to elastic inter- 
action between interstitials and screw dislocations leading; to cross- 
slip, whereas softening in substitutional alloys is attributed primarily 
to electronic interaction, i.e., modification of the <i-band density leading 
to reduction of the Peierls-Nabarro energy barrier. The relationship 
between alloy softening and the ductile-to-brittle behavior of bcc 
transition metals is being explored in high-purity interstitial alloys 
of iron. 

Microplasticity in Metals — Microplasticity studies at room tem- 
perature on tensile specimens of 4340 steel in the conditions as 
normalized and as quenched and tempered to a tensile strength of 
273,000 psi, and on a specimen of annealed Invar have revealed (1) 
that the practice, commonly employed, of prestraining a specimen 
before conducting microplasticity tests introduces appreciable in- 
stability of the specimen, and (2) the microplastic behavior of the 
prestrained specimen, especially at very small strains ranging from 
1 X 10~ 7 to 1 X 10 -4 , is not representative of that of the specimen in 
its initial heat-treated condition. 

High- Temperature Creep — An NBS-designed-and-constructed ma- 

124 



chine has been installed and is being used to facilitate the study of 
the mechanisms underlying creep. Controlled through an analog com- 
puter, it provides a constant resolved shear-stress loading to single 
crystals compensating for slip-plane rotation and reduced cross section. 
It also has the capability of producing rapid temperature and stress 
changes and can operate in either high vacuum or inert atmosphere. 

Ultrasonic Measurements in Molten Glass— It has been difficult, if 
not impossible, to perform high-temperature shear ultrasonic relaxa- 
tion spectroscopy in molten glasses because of the high absorption of 
shear waves in the liquid. These structural investigations have been 
aided by improved ultrasonic detection using a phase-locking tech- 
nique. A technique using signal-averaging and synchronized discrimi- 
nating amplification common to sonar and some light-scattering 
experiments was modified for the purpose. This resulted in an increased 
range of absorption per wavelength of more than twice that of pre- 
viously reported equipment. One inexpensive lock-in amplifier and a 
few general laboratory instruments can be easily incorporated into 
all ultrasonic systems with a video output, and will enhance signals 
of any E. F. frequency by approximately 25 dB, and increase the 
accuracy of amplitude measurements to about 0.1 dB. This added 
range enabled the study of shear ultrasonic relaxation spectra in mol- 
ten glasses, and opened up a new research area : the ultrasonic detec- 
tion of molecular clusters in immiscible oxide glasses. 

Optical, Electrical, and Magnetic Properties 

Vacuum Ultraviolet Excited Fluorescence — The fluorescence of 
chlorine produced from the vacuum ultraviolet photolysis of phos- 
gene has been observed. From the dependence of the fluorescence upon 
the wavelength of the exciting radiation, it has been concluded that 
literature values for the electronic energies of two of the upper excited 
states of chlorine are too high by as much as one electron volt. It should 
be noted in this instance that a well-designed photochemical experi- 
ment has yielded results which are of primary concern to the molecular 
spectroscopist. It is an excellent example of how different disciplines 
interact in an active research area such as photochemistry. 

Organic-Dye Lasers — IMK physical chemists have recently insti- 
tuted a study of the properties of organic-dye lasers. The main empha- 
sis of the program is on studying the mechanism of the laser process 
and the role of molecular triplet states in reducing the efficiency of 
the system. Theoretical calculations indicate that the addition of 
quenching agents specific for triplet states should greatly increase the 
efficiency. Experiments are in progress to test the validity of these 
calculations. A giant flash-photolysis system has been used to pump 
rhodamine 6G, and outputs in excess of 1J and pulse-lengths of 30 to 
40 fi s have been obtained. 

125 



Optical and EPR Study of Orange Ruby — Orange discoloration 
has been a source of degradation in performance sometimes encoun- 
tered in ruby lasers. A number of doped sapphire crystals have been 
grown and studied in this laboratory. Dopants include Cr (i.e., ruby) 
and other single-transition elements, and combinations including Cr 
as the second dopant. Optical absorption spectra taken before and 
after x-ray coloration show that the discoloration spectra produced 
are similar to those reported in laser rods, but only when Cr is present. 
Double-doping with Cr plus Mg produces the orange color without 
irradiation, and irradiation produces only a slight additional increase. 
Valence considerations suggest that the phenomena involve either a 
change of Cr valency or color centers or both. EPR spectra are being 
taken on a number of these samples in an effort to observe and identify 
the defects responsible. 

Thermo-Optic and Piezo-Optic Properties of Laser Materials — ■ 
The changes in refractive index caused by temperature and hydrostat- 
ic pressure have been determined for five neodymium-doped glasses 
and single-crystal ruby by an optical interference method. It is inter- 
esting to note that for ruby there is a decrease in refractive index for 
both the ordinary and extraordinary ray with applied hydrostatic 
pressure. Furthermore, there is an increase in refractive index with 
rise in temperature. These changes are not what might be expected 
on the basis of density considerations. Using the method of uniaxial 
loading in conjunction with the application of hydrostatic pressure, 
the two piezo-optic and two elasto-optic coefficients of each of the five 
glasses have been determined. The eight piezo-optic and eight elasto- 
optic coefficients of single-crystal ruby have also been determined. 

These data are of immediate interest in laser technology because the 
temperature-induced changes in refractive index create a distortion of 
the wavef ront of light generated in a laser solid. Since the refractive 
index is dependent on temperature, there is a direct change caused by 
the temperature gradient from the center to the edge of the rod. In 
addition, the temperature gradient creates internal stresses which pro- 
duce further changes in index arising from the stress-optic effect. 
There are virtually no data in the literature on the temperature and 
stress coefficients of the refractive indices of important laser materials. 

Plasmaron Structure in the Soft X-Ray Spectrum of Al — As part 
of a continuing study of the density of states in metals, the L 2( 3 soft 
x-ray emission spectrum of Al has been carefully scanned for a low- 
energy edge due to a plasmon interacting resonantly with a hole 
(called a plasmaron), predicted by recent theoretical studies of the 
interacting electron gas. A very weak structure near the predicted 
location, but just within the noise level, was seen. An upper limit to 
the magnitude of such structures was established and it was sug- 
gested that the light alkali metals should provide a better test of the 
theory. 

126 



Refractive Index of Cuprous Chloride — The refractive index of 
single-crystal cuprous chloride (CuCl) was measured at room tem- 
perature in the wavelength range 0.42 /mi to 22 /xm. CuCl is a poten- 
tially important laser-modulator crystal by virtue of its large electro- 
optic coefficient. Because it is cubic it lacks the undesirable feature 
of natural birefringence present in all commercial modulator ma- 
terials. In addition, CuCl is transparent to beyond 20 /xm, making 
it useful for modulating the intensity of the C0 2 laser at 10.6 /xm. 
The measurements were performed in the wavelength range 0.42 /xm 
to 1.2 /xm with a commercial V-block refractometer. The range of 
wavelengths was extended to 22 /xm by measuring the wavelength- 
dependence of interference fringes in thin polished plates. Materials 
were supplied by the Air Force Cambridge Research Laboratory and 
the Massachusetts Institute of Technology. 

Infrared Absorption in Perovskites — The optical absorption spec- 
trum of SrTi0 3 has been examined over the wavelength range of 
2.5 /*m to 25 /xm. Nine broad absorption bands were observed beyond 
3 /xm, and a set of sharp lines at 2.86 /xm. The sharp lines are inter- 
preted as due to OH impurities in the crystal, while the broad bands 
are believed to be due to multiphonon creation processes, except for 
one which is a single-phonon process. Selection rules for simultaneous 
creation of either two or three phonons were obtained, in dipole ap- 
proximation, at selected critical points in the Brillouin zone. The 
observed bands were assigned, using these rules together with the 
experimental phonon-dispersion curves of Cowley and other published 
values for the higher-energy branches obtained at specific points in 
the zone by other techniques. Some of the phonon energies determined 
in this way have not been seen by neutron diffraction techniques. The 
results are typical of what is observed in other perovskite-type ma- 
terials such as LiNb0 3 , KTa0 3 , and BaTi0 3 . 

Structural and Spectroscopic Properties of Nickel (I I) Pyrazole 
Complexes — X-ray diffraction and visible spectroscopic studies have 
been carried out on single crystals of some pyrazole complexes of 
nickel (II). The electronic-energy levels in two halogen-substituted 
complexes were shown to differ markedly from those in the closely re- 
lated pyridine complexes. Detailed crystal-structure data showed that 
the unusual energy-level systems in these complexes were related to 
internal hydrogen bonding between the coordinated pyrazole mole- 
cules and the coordinated halogen atoms. The spectral assignments 
were based on a reduced effective field of the halogen atom at the site 
of the nickel (II) ion. These assignments were corroborated by the 
observed bond distances and pyrazole ring orientations. 

Thin-Film Dielectric Measurements — Developments in the com- 
mercial manufacture of thin polymer films have generated considerable 
interest in the use of these films as electrical insulators. This interest 

127 




Three-terminal fluid displacement cell used to measure dielectric properties and 
average thickness of their films. 



has resulted in a joint program between IMR scientists and a research 
scientist from FMC Corporation. A three-terminal fluid-displacement 
cell was designed and built and is being used to successfully measure 
the dielectric properties of commercial films as thin as 0.025 /mi. Not 
only does the two-fluid method used with this new cell permit dielec- 
tric constant measurements on a 25 -/mi film with an accuracy of better 
than 1 percent, but it also provides a unique way of measuring the 
average thickness of these films with an accuracy of the order of 1 
percent. This program has resulted in significant advances in measure- 
ment capability that will be used by industry in the evaluation of 
insulating films and by NBS for the development of thin-film reference 
standards of dielectric constant and thickness. 

1)1 pole Moments of Molecules in the Vapor Phase — An unconven- 
tional method for precise determinations of clipole moments of sym- 
metric top molecules in the vapor phase has been used to obtain data 
on reactive gases with small dipole moments. The method is based 
on experimental measurements of the shape of the nonresonant Debye- 



128 



type microwave absorption in pure gases and gas mixtures. The 
measurements are made by varying the pressure at a single tempera- 
ture where the gas is chemically and thermodynamically stable. The 
errors due to temperature variation are eliminated, and the sensitivity 
of the method permits determination of dipole moments too small to 
be detected by conventional methods. 

Low-Field Tri-axial Helmholtz Coils — A circular, triaxial, fourth- 
order, air-core, Hehnholtz-coil system was designed and constructed 
with the aid of the Navy Bureau of Weapons. The coil system was 
designed so as to generate a magnetic field homgeneous to 1 part in 
10 4 over a volume of nearly 100 cm 3 . This coil system will be used for 
the calibration of magnetic flux density measuring equipment, and 
in a study of the feasibility of using electron paramagnetic resonance 
as a primary standard of magnetic flux density in the range of 0.1 to 
80 millitesla. 

Iron Nuclear Magnetic Resonance in Paramagnetic TiFe and 
TiFe-TiCo Alloys — For the first time in any paramagnetic material, 
the nuclear magnetic resonance of 5T Fe has been detected. The dis- 
co very was made by a team of IMR scientists including an NBS 
industrial research associate from the U.S. Steel Corporation. The 
team used the combined facilities of U.S. Steel laboratories for sample 
preparation and NBS laboratories for the resonance work. Each of 
the two samples used, enriched in the stable isotope r,7 Fe, is valued at 
$6,000. 

Although the nuclear magnetic resonance is observed with relative 
ease in ferromagnetic materials due to a signal enhancement related 
to the magnetic domains, this observation demonstrates that it is 
also possible to observe the 57 Fe nuclear magnetic resonance in para- 
magnetic materials as well. This resonance is being used to study the 
electronic properties of TiFe and TiFe-TiCo alloys. These alloys are 
structurally related to TiNi, which has an unusual mechanical memory. 

Precision High-Pressure Measurements Via N.Q.R. Spectroscopy — 
Pressure measurements up to 2 kbar have been made with a precision 
of ±0.5 bar. This has been done using a servo-controlled nuclear 
quadrupole resonance spectrometer and a carefully purified sample of 
KC10 3 . The main source of error at the present time arises from the 
small temperature fluctuations (±0.005° C) of the high pressure 
vessel. 

Reactivity and Corrosion 

Anisotropic Oxidation of Pyrolytic Graphite — Pyrolysis of a hy- 
drocarbon at low pressure and high temperature can be used to 
deposit a form of polycrystalline graphite with preferred orientation. 
As a result of the orientation, with graphite basal plane preferentially 

129 



parallel to the surface of the substrate, anisotropy of physical and 
chemical properties is evident. IMR scientists have measured the ratio 
of air oxidation of graphite for rates parallel to and perpendicular to 
the preferred basal plane direction. From 800 to 1800 K, the ratio 
increases from about one to seven, with the faster oxidation parallel 
to the preferred basal plane direction. The offered explanation sug- 
gests that the same two-stage mechanism is involved in both direc- 
tions: chemisorption followed by decomposition of surface oxides. 
The surface concentration of available sites is sufficiently different, 
however, that in one case the chemisorption is rate-limiting and in 
the other decomposition is limiting. This interpretation leads to activa- 
tion energies in agreement with literature values for both steps of the 
mechanism. 

Catalytic Decomposition of Hydrazine — Hydrazine and some of its 
derivatives are of interest as rocket fuels. However, hydrazine decom- 
poses catalytically when stored in some metal containers, such as 
maraging steel. Investigations by IMR scientists show that the 
catalytic decomposition can be reduced to an insignificant rate by 
certain coatings electro-deposited on the steel. Among the best for the 
purpose are cadmium, silver, electrodeless nickel, and tin-lead alloy. 

Stress-Corrosion Cracking of Glass — Glass is usually regarded as 
an inert material, being highly resistant to chemical corrosion. As a 
result it finds use as liners in water heaters, in industrial plants where 
chemical resistance is important and in the laboratory. Despite this 
well-known resistance, glass is susceptible to stress-corrosion cracking 
by water. The effect is so severe that, all other things being equal, the 
strength of glass is reduced by about 80 percent in the presence of water 
or water vapor. 

Stress-corrosion in glass, as in other materials, results from the slow 
growth of surface cracks due to stress and environment. In glass the 
phenomena is believed to be due to a chemical reaction between the 
glass structure and the water molecules. The rate of reaction can be 
monitored by measuring the rate of crack growth as a function of 
temperature, applied stress, and environment, and the data obtained 
can be used to describe the process in fundamental terms used in 
reaction-rate theory. During the past few years the Institute for 
Materials Research has been conducting such experiments using 
fracture-mechanics techniques. Conclusions from such experiments are 
as follows : 

1. Crack-velocity data quantitatively satisfies the Charles-Hillig 
theory for stress-corrosion of glass. 

2. Glasses of different chemical behavior exhibit varying degrees of 
resistance to stress-corrosion cracking. 

3. In water, the rate of reaction of hydroxyl radicals with the glass 
appears to control the rate of crack-growth. 

130 



4. In gaseous nitrogen containing water vapor, there are three 
distinct mechanisms of crack-growth. At low-stress intensity levels 
the rate of crack-growth is reaction-rate limited. At intermediate 
levels, the rate of crack-growth is limited by the rate of water trans- 
port to the crack tip. At the highest stress-intensity levels, crack- 
growth is independent of environment. 

Stress-Corrosion Cracking of Copper Alloys — In a joint effort at the 
1MB, laboratories, a research associate from the Besearch Institute 
for Advanced Studies (a division of Martin Marietta) and an 1MB 
scientist have provided data that supports, in part, a stress-corrosion 
cracking theory. The theory proposes that the stress-corrosion crack- 
ing of alpha-phase copper alloys in tarnishing ammoniacal solu- 
tions proceeds discontinuously by the repeated formation and rupture 
of a brittle tarnish film. An important prediction of this "brittle-film" 
mechanism is that the cracking rate is determined by the rate of growth 
of the tarnish film. Earlier work on the alpha-brasses established that 
the cracking rate increases with increasing zinc content of the solid, 
w T ith increasing temperature, and with the application of anodic 
potentials, but qualitative data was not available. 

The ellipsometric data from the present study demonstrated quan- 
titatively that the rate of tarnish growth increases significantly with 
zinc content, as does cracking rate. For example, the time taken for 
the film to attain a thickness of 900 A was found to be 44 min for 
pure copper, 16 min for Cu-5 Zn, 317 min for Cu-10 Zn, 1 min for 
Cu-20 Zn, and ^ 1 is for Cu-30 Zn. The rate of tarnish growth deter- 
mined quantitatively was also found to increase with increasing tem- 
perature and with applied anodic potentials, as does cracking rate. 

Pure cooper, which is not susceptible to stress-corrosion cracking in 
ammoniacal solutions, was found to have a low (less than alpha- 
brasses) film-growth rate. Further work is needed to explain why 
copper does not undergo stress-corrosion cracking in this solution. 

Initiation of Pitting of Iron — Studies sponsored by the Office of 
Saline Water have shown that before the protective (passive) films on 
iron break down in the presence of chloride ions, subtle changes occur 
in the optical properties of the films. These changes occur before the 
ordinary indications of breakdown (e.g., an increase in current via 
galvanometric measurements) signal the onset of pitting. The changes 
in film properties, triggered by chloride ion, have been detected by 
ellipsometric spectrometry — a new technique which enables the meas- 
urement of optical spectra of very thin films on metal surfaces while 
they are immersed in solution. These studies are important in eluci- 
dating the mechanism of the pitting of metals, which is responsible for 
many corrosion failures. 

Corrosion of Titanium Alloys — Studies of the initial stages of cor- 
rosion in a series of titanium alloys are in progress, using electron 

131 



: 




An electron transmission micrograph taken from a thin specimen of a titanium- 
palladium after corrosion in a salt-water solution. A thin film of titanium oxide 
containing small oxide crystallites is seen superimposed over the microstruc- 
ture and grain boundaries in the alloy specimen. 



microscopy and diffraction techniques. At the same time, quantitative 
chemical analysis of microscopic areas is proceeding using an electron 
probe micro-analyzer. The influence of high temperatures and pres- 
sures, using a salt-water corroding solution, are being investigated. 
Extremely thin corrosion films can be Studied either in place on the 
alloy specimens or after removal to determine the physical and chemi- 
cal nature of the films. The relative resistance to corrosion of the 
various alloys is interpreted in terms of the microstructure and chemi- 
cal composition of the specimens. The results of these studies should 
guide the choice of the most suitable materials for applications to 
salt-water purification plants. 

Microbiological Corrosidn of Iron — A marine strain of Desulfovi- 
hria has been isolated which produces a mixture of schreibersite 
(Ni, Fe) 3 P, and iron sulfide when grown in a sea water medium con- 
taining ferrous ions and organic material. Schreibersite and iron 
sulfide (trolite) are found to be closely associated in certain meteorites 
and tectites. 

The anaerobic corrosion of iron in the same medium without added 
ferrous ions was associated with removal of a protective iron sulfide 
film formed during growth of the organisms. 

Corrosion of Steel Piles in Underground and Seawater Environ- 
ments — The most extensive corrosion test programs ever undertaken 
are under way to determine the best means of protecting steel piles 
from corrosion. Measurements of corrosion rates are being made 
periodically on steel pile specimens exposed underground and in 

132 




Corrosion rates of steel pilings exposed underground and in seawater are being 
studied to determine optimum means of corrosion protection. Polarization tech- 
niques are used to measure instantaneous corrosion rates of the specimens. 



seawater. Polarization techniques developed in the laboratory at NBS 
are being applied to monitor the instantaneous-corrosion rates of the 
steel pile specimens. 

The study is planned to extend over a 15-year period in the seawater 
site and 25 years in the underground site. It is expected that the results 
will show a correlation between the amount of corrosion on the steel 
test piles, as determined by polarization measurements, and the actual 
corrosion on the specimens which will be measured when the test piles 
are extracted from the test sites after specific exposures. 

In the seawater site, over 100 carbon-steel and low-alloy steel piles 
(35 ft long, 45 lb/ft) were installed 19 ft into the Atlantic Ocean 
bottom off the coast of Dam Neck, Virginia. Many types of protective 
methods are included in the investigation, ranging over coating sys- 
tems (coal-tar epoxy, galvanized, aluminum- and zinc-flame spray, 
zinc-rich paints, etc.,) and cathodic protection by zinc and aluminum 
sacrificial anodes. 

In the underground sites, 21 steel piles (35 ft long, 74 lb/ft) were 
driven to bedrock in connection with the construction of a Trans- 
canadian Highway Interchange in Montreal, Quebec, Canada. 

Cooperating with NBS in these investigations are the American 
Iron and Steel Institute, Province of Quebec, the U.S. Army Coastal 
Engineering Eesearch Center, the U.S. Navy Civil Engineering Lab- 
oratory, Amphibious Forces, and the Fleet Antiwar Aircraft Training 
Center. 



133 



Engineering Materials 

Impact Properties of J^Sl Stainless Steel — The inclusion of refrigera- 
tion in the heat-treatment of 431 stainless steel has been a common 
practice. Data obtained in an investigation of the effects of refrigera- 
tion and strain on the notch toughness of 431 indicate that refrigeration 
should be avoided in the heat-treatment of 431 parts subjected to stress 
concentration or impact loading. 

Fatigue O racking in Chromium Diffusion-Coated Ti-B earing 
Steel — Chromium diffusion coatings on Ti-bearing steel frequently 
lead to columnar growth beneath the Cr-rich layer. The grains are 
preferentially oriented. The depth of the columnar zone does not 
depend on the chromizing time. A high rate of cooling prevents col- 
umnar growth. No grain-boundary diffusion or carbide formation at 
the grain boundaries was observed. The Cr-rich layer is structurally 
homogeneous and consists of a-solid solution. The hardness of the 
coating does not vary with the chromizing time. 

Dimensional Stability of Gage-Block Steels — The causes of dimen- 
sional instability in a 52100-type steel hardened to R c 65 are being 
investigated and several important facts are indicated. Precision elec- 
trical resistance measurements, microhardness measurements, and car- 
bide determinations indicate that the measured parameters change 
with long aging-time, and that these changes can be correlated with 
length changes. The results tentatively indicate that three structural 
processes are occurring : dissolution of carbides, diffusion of carbon to 
lattice imperfections, and re-precipitation of carbides at new sites. 

Properties of Electrodeposited Copper — A comprehensive investi- 
gation of the properties of electrodeposited copper, in progress for five 
years, has been completed. During the past year the large amount of 
data has been compiled into numerous tables and graphs and the com- 
plete work prepared for publication. 

The project was sponsored jointly by the American Electro-platers' 
Society, the International Copper Research Association, the Copper 
Development Association, and the National Bureau of Standards. In- 
vestigations covered the types of plating baths used in industry : acid 
sulfate, cyanide, pyrophosphate, fluoborate, and amine baths. A num- 
ber of properties were measured on each type of deposit obtained under 
about 150 different sets of operating conditions, the latter comprising 
variations in bath composition, temperature, and current-density. 
Properties measured and correlated included: tensile and yield 
strengths, modulus of elasticity, elongation, internal stress, fatigue 
limits, hardness, density, electrical resistivity, thermal expansivity, 
structure, and chemical composition. Effects of cold- working and 
annealing, and effects of cryogenic and elevated temperatures on some 
of the above properties, were also determined. 

134 



Development of a Radiopaque Composite Dental Restorative Ma- 
terial — Radiopaque esthetic direct filling materials are needed to 
facilitate dental radiographic diagnosis. An x-ray-opaque composite 
restorative material was developed having adequate esthetic properties 
for use in anterior teeth. The resin binder is a ternary eutectic climeth- 
acrylate formulation. The powder consists of a BaF 2 _ containing glass 
and fused silica both treated with a silane coupling agent and con- 
taining peroxide initiators. 

One hundred and ten restorations were placed using this newly de- 
veloped material. The restorations will be observed over a prolonged 
period. They had sufficient radiopacity and yet were esthetically 
pleasing. 

Spherical Alloy for Dental Amalgam — A significant improvement 
in the physical properties of silver-tin-mercury alloys used in restora- 
tive dentistry has resulted as a culmination of research conducted at 
NBS. In this study, irregularly shaped particles formerly used to 
prepare dental amalgam alloys have been replaced by spherical alloy 
particles with a consequent improvement in strength and durability. 
In addition, the alloys can be packed into the tooth cavity with less 
pressure, resulting in greater comfort and convenience for both the 
dentist and his patient. The new alloy has recently been marketed both 
in this country and abroad. 



iff vm " * : 



w.Wk 



sggF 






w l 




Photomicrograph of dental amalgam alloy prepared with spherical alloy particles. 



135 



Gallium Alloys for Restorative Dentistry — A gallium-tin-pallad- 
ium alloy has been developed which may be substituted in place of 
the mercury-tin-silver alloys now used to replace tooth structures 
lost as a result of caries. The new alloy is 50 percent stronger, several 
times more resistant to flow under an applied load, and has a thermal 
expansion coefficient closer to that of human teeth than the present 
dental amalgam alloys. In addition, this alloy wets tooth structure 
and thereby produces a more effective seal against fluid infiltration 
at the margins between the filling and the tooth. The alloy requires 
extensive biological and clinical testing before it can be made avail- 
able for extensive use. 

Creep of Pure-Gum Vulcanizates of Natural Rubber — The creep 
of vulcanizates of natural rubber cured with varying amounts of 
dicumyl peroxide was compared with that of vulcanizates cured by 
typical conventional sulfur-accelerator systems. The measurements 
involved indentation of a flat rubber disk as a function of time t and 
temperature T. The product of shear compliance J and T as a func- 
tion of log t was represented by a family of curves with T as the param- 
eter. For the vulcanizates cured with the sulfur-accelerator system, 
previous work has shown that the individual curves could be shifted 
along the abscissa to yield a single continuous curve with a slope which 
increased from a negligible value to a maximum and then decreased, 
continuing through a region of minimum slope extending over about 7 
decades of time before ending in a region of increasing slope. The 
value of the creep was 1.5-2.0 percent per decade in the region of 
minimum slope. When the same procedures were applied to the vul- 
canizates cured with dicumyl peroxide, the individual curves of JT 
against log t at each temperature did not yield a single continuous 
curve when shifted. In a limited region just above the glass transi- 
tion temperature, the creep was appreciable, but neither a constant- 
activation-energy shift nor a Williams-Landel-Ferry shift was satis- 
factory. Above this region it was clearly impossible to obtain a 
single curve, since the compliance-temperature product at a given 
time increased with increasing temperature while the corresponding 
creep of the dicumyl peroxide vulcanizates was generally too small 
(<0.5% per decade) to be measured between 5 s and 600 s, except 
when the compound contained less than 2.5 parts of effective dicumyl 
peroxide. Outside of these regions the shear modulus was found to 
increase linearly with temperature. The investigation included tem- 
peratures as high as 100 °C and effective dicumyl peroxide concen- 
trations as high as 25 parts per hundred of rubber. 

TECHNICAL ASSISTANCE TO OTHERS 

IMR gives technical assistance and advice on materials to other 
Government agencies, and to science and industry. Arranging con- 

136 



ferences and seminars to facilitate dissemination of new data useful 
in solving materials problems is also an important service provided. 

Advisory and Consulting Services 

Life of Postage-Stamp Printing Plates Increased — Although prior 
recommendations of NBS have resulted in improved life of postage- 
stamp plates used by the Bureau of Engraving and Printing, a break- 
through in this area has been made. By judicious shot-peening of 
selected portions of the back of the plates, fatigue-resisting compres- 
sive stresses have been introduced and machining irregularities 
removed. The results on lifetime has been to increase service-life by 
more than an order of magnitude. One test plate now in service has 
registered 1,700,000 impressions and is still serviceable. This contrasts 
with untreated plates which may fail at less than 100,000 impressions. 

Carbon Dioxide Standards — IMR chemists have developed a highly 
accurate gravimetric technique to prepare three standards of carbon 
dioxide in air for the Environmental Science Services Administration. 
The compositions were ascertained to within one part in ten thousand, 
and the mixtures will serve ESSA as primary standards for the 
continuing investigation of atmospheric composition. 

Calibration Standards for Salinometers — The conductivities of 20 
samples of sea water of varying salinities were measured for the De- 
partment of the Navy. These samples will be used for the calibration 
of oceanographic salinometers. The same techniques were also used 
to measure the conductivities of two different lots of Standard Sea 
Water with an accuracy of 50 ppm. Standard Sea Water is a con- 
venient and widely accepted reference for oceanographic measurements 
but is available at only one value of salinity. 

Conferences and Symposia 

Symposium on the Structural Properties of Hydroxy apatite and 
Related Compounds — Sponsored jointly with the Office of Naval Re- 
search, in cooperation with the American Dental Association and the 
Georgia Insitute of Technology, this symposium revieAved critically 
the information available on apatites. The properties of these com- 
pounds have importance in diverse areas such as tooth, bone and 
pathological mineralizations, minerals, fluorescent coatings, water 
purification, and oceanography. Twenty papers were presented and 
125 visitors participated in the symposium. The papers are to be 
published as a text. 

Symposium on the Thermodynamic Properties of Bulk Polymers — 
Through its Polymers Division, the Institute for Materials Research 
sponsored this symposium at the NBS Gaithersburg Laboratories on 

137 



March 10-12, 1969. The symposium assembled over a hundred polymer 
scientists from industrial, university, institutional and governmental 
laboratories to focus discussion on the specific aspects of polymer 
science indicated by the symposium title. Thirty papers were discussed 
on subjects including: crystalline, vitreous, and elastomeric physical 
states; crystallization, melting, glass transformation, and other physi- 
cal transitions and relaxations; elasticity of elastomers; special 
methods for determining thermodynamic properties ; state properties 
and their derivatives for common and special situations; and the 
relationship between thermodynamic and molecular properties. 

Symposium on Ion-Selective Electrodes — This symposium, held at 
NBS on January 30-31, 1969, was attended by approximately 450 
physical and biomedical scientists. The present state of the art and 
future capabilities of these electrochemical sensors were evaluated. A 
broad spectrum of topics ranging from principles, characteristics and 
basic chemical studies to applications in biomedicine and industrial 
analysis and control was reviewed. The published proceedings of this 
symposium, consisting of the complete texts of the invited review 
papers plus selected segments of the panel discussions, is available 
from the Government Printing Office as NBS Special Publication 
314. 

Modern Trends in Activation Analysis — The Third International 
Conference on Modern Trends in Activation Analysis, sponsored 
jointly by the National Bureau of Standards, the U.S. Atomic Energy 
Commission, the International Atomic Energy Agency, and EURI 
STOP, European Communities Commission, was held October 7-11, 
1968. The Conference was attended by over 400 scientists, including 
100 from countries other than the United States. Each day a plenary 
lecture, given by a recognized world authority, outlined the state-of- 
the-art for the various phases of activation analysis. This lecture was 
followed by simultaneous sessions with contributed papers. A panel 
discussion at the end of each day's sessions provided a synopsis of 
the major points of discussion in each session, allowing attendees to 
hear the highlights of sessions they were unable to attend. More than 
150 technical papers were presented. The published Proceedings of the 
Conference are now available. 

Conference on Fundamental Aspects of Dislocation Theory — Held 
at NBS under the auspices of IMR on April 21-25, 1969, this confer- 
ence was devoted to a thorough appraisal of dislocations in crystals. 
One hundred theorists from 18 different countries attended to center 
on the questions : "How far have we come ?" and "Where do we go from 
here?" Seventy papers were presented, ranging over all aspects of the 
subject including its applications to mechanical properties of materials, 
lattice mechanics of defected crystals, biophysical applications to pro- 
teins, and liquid crystals. The published proceedings are expected to be 
available in the spring of 1970. 

138 



Symposium on " Nuclear Standards for Chemistry and Technology — 
This Symposium was held September 8-9, 1968, sponsored jointly by 
the American Chemcial Society's Division of Nuclear Chemistry and 
Technology and the ACS Committee on Standardization Relations. 
The Symposium was organized to bring workers in the diverse areas 
of safety, health, quality assurance, and specific engineering stand- 
ards together to discuss present programs and future needs in the 
relatively new and rapidly growing field of nuclear technology. The 
published proceedings of the Symposium are available as NBS Spe- 
cial Publication 310. 

"Symposium on an International Standard Reference Materials Pro- 
gram" — This Symposium was held May 26-28, 1969, at the National 
Bureau of Standards, under the joint sponsorship of NBS and the 
International Committee on Weights and Measures (CIPM). Thirty- 
three representatives from 15 countries and 4 international agencies 
attended. The goal of this first International Standard Reference 
Materials Symposium was to explore the possibilities and problems 
of an international SRM Program. A summary of the Symposium dis- 
cussions is being published in Metrologia. 



375-572—70 10 139 



INSTITUTE FOR APPLIED TECHNOLOGY 

The Institute for Applied Technology (IAT) attempts to meet the 
Nation's need for measurements and standards related to the artifacts 
of our society. Thus, the IAT programs are concerned with techno- 
logical or "engineering" measurements and standards which deal with 
products, commodities, devices, processes or systems. These measure- 
ments and standards are the language of the market place for coupling- 
user requirements with the performance capabilities of products, proc- 
esses or devices, and thus bring order and quantification to man's 
use of his technical skills. 

The Institute provides a technical base for the development of en- 
gineering and product standards, and measurement methodology. Its 
programs are oriented to industry, to the States and regions of the 
country, and to all levels of Government. They bridge the interface 
between science and its applications, and by coupling science and tech- 
nology with the daily activities of commerce, industry, and Govern- 
ment, they stimulate economic progress. 

The Institute is responsible for several mandatory legislative assign- 
ments. Among them are the Flammable Fabrics Act as amended in 
1967, the Fire Research and Safety Act of 1968, and the Fair Pack- 
aging and Labeling Act. 

IAT activities fall into two major categories: Technological Meas- 
urements and Standards, and Technical Innovation. A substantial 
part of the work done in the IAT program is technical assistance to 
other parts of the Bureau, other Government agencies, and to industry. 
Work done in motor vehicle safety research and technical analysis is 
virtually all done in support of the mission of other agencies of Gov- 
ernment. In other fields, a lesser but still substantial volume of IAT 
work is done at the request of others. 

TECHNOLOGICAL MEASUREMENTS AND STANDARDS 

This category covers the Institute effort for the broader extension 
of the national measurement system into the engineering and techno- 
logical fields. It is a program to apply principles of good measurement, 
rather well defined in the science area, to the determination of per- 
formance or other significant characteristics of products systems and 

141 



devices important either in Commerce or to Government needs. In 
essence, the objective is to find ways by which standards or a national 
and sometimes international consensus of measurement methodology 
can be developed for items, systems, and devices which are not readily 
evaluated in terms of existing measurement methods. 

The performance concept introduces man into the measurements 
and standards process, and the whole idea centers on the belief that 
products, processes, services, and systems can be described and their 
performance can be measured in terms of user's requirements without 
regard to their physical characteristics, design, or method of their 
creation. Key to this method is the identification of measureable per- 
formance criteria for meeting the user's requirements, thereby cou- 
pling subjectively derived needs with objective technical measure- 
ment methods. 

As the complexity and technical sophistication of articles of com- 
merce increase, it becomes increasingly difficult to define those charac- 
teristics of a product which best measure its performance. The virtue 
of the performance concept in measurement and standard develop- 
ment is that it stresses the end to be attained, and leaves the means to 
obtain the desired end wide open. 

Today many complex products are actually complete "systems," 
and the only feasible way to evaluate them is in terms of their per- 
formance against criteria established to meet the user's require- 
ments. The concept encourages innovation when producers can meet 
the performance required by whatever design of product will do the 
job. 

The idea of performance criteria also has ramifications beyond 
those concerned with articles of commerce. Our national welfare de- 
pends critically on making informed decisions related to complex 
social and economic policies and programs. To do this, one needs to 
define criteria of performance for these policies and programs and 
be able to measure or predict possible benefits and costs of alternative 
actions. Through the techniques of system analysis and operations 
research, technology has provided a means for helping such decision- 
making. 

Institute activities in technological measurements and standards 
range from the development of performance criteria and test methods 
for individual items to the study and analysis of complex systems 
such as a multi-State transportation network. 

During the past year several organizational changes were made 
to concentrate the Institute efforts in the technology area. The Center 
for Computer Sciences and the Clearinghouse for Scientific and 
Technical Information were separated from IAT. In addition, a prod- 
uct testing laboratory developed for the General Services Administra- 
tion (GSA) was transferred to GSA. Added to the Institute were a 

142 



Measurement Engineering group and an Instrument Shops group. 
The Institute inaugurated an Office of Fire Kesearch and Safety with 
responsibility for planning the programs anticipated when funds be- 
come available under the terms of the Fire Research and Safety Act 
of 1968. 
Program elements include: 

Technological Measurements and Standards 

Building Technology 

Electronic Technology 

Systems Analysis 

Motor Vehicle Safety 

Engineering Materials 

Industrial and Consumer Products 
Technological Innovation and Diffusion 

Invention and Innovation 

Building Technology 

The spiraling of construction costs combined with the tremendous 
backlog of housing units required to be produced in the next 30 years 
have accelerated the move to the industrialization of the building 
process. This change, from an industry heavily dependent on hand 
craftsmen techniques, to one of mass-production is generating pres- 
sures for up-dated standards, improved techniques for determining 
user requirements, and advanced capability for evaluating the per- 
formance of complex components. In order to meet this demand, the 
NBS programs for building technology have been broadened to cover 
more than the traditional materials research, which alone is no longer 
adequate to provide answers for the new questions raised by indus- 
trialization of the building process. All of these questions involve a 
consideration of cost to some extent. Therefore, this broadened scope 
must include studies of building economics. The program of economic 
studies has been initiated as a multiagency project, designed to develop 
a computerized construction cost control system that relates unit build- 
ing prices, operation, and maintenance costs. This information can be 
used to project estimates of both building and operating costs from 
preliminary planning, through construction, to ultimate building use. 

The scope of research in building technology in the past year was 
expanded by the creation of a "Sensory Environment Branch" with 
three sections, namely; Environmental Engineering, Psychophysics, 
and Building Transport Systems Section. The environmental engi- 
neering program will continue the work which has been going on 
with regard to the materials and equipment which create the favor- 
able interior environment of buildings. The psychophysics program 
will study techniques for evaluation and measurement of the responses 
of building occupants to the visual, aural, thermal, and spatial char- 

143 



acteristics of the interior environment. The transport systems program 
will gradually he enlarged from plumbing activity to include elec- 
trical and communications systems, and food, water and fuel distribu- 
tion, and movement of people. A "Mobile Acoustical Laboratory" 
has been acquired. This laboratory can be used at the site of existing 
structures. 

The application of advances in building technology depends on 
dissemination of new information as it is developed. NBS has hosted 
or sponsored conferences, seminars, and symposia held throughout the 
year to this end; such as: Man and His Shelter — Roofing Tech- 
nology — Durability of Insulating Glass — Wind Loads. ... It is an- 
ticipated that there will be larger numbers of such conferences in the 
future. 

A new program in urban technology has been initiated to develop 
an information framework of user needs for housing, especially for 
low -income housing. The questions to be examined include what infor- 
mation is germane, how it may be manipulated, where it falls in 
relation to other information, when it is applicable, and to whom it per- 
tains. Criteria for user needs are derived from all sources in dividing 
the fields of sociology, physiology, and psychology. Where criteria 
cannot be developed from these sources, the program will develop 
substitute evaluative techniques and a basis for judgment decisions. 

The building technology program continued the traditional labora- 
tory and field support provided to Federal agencies, State, and local 
Government groups concerned with building construction and tech- 
nology. Technical consultation and advice was made available to in- 
dustry, and the staff continued to work closely with the many private 
standards-making groups throughout the country. 

Outdoor Exposure of Building Materials — The Building Research 
Division completed the establishment of six outdoor sites for testing 
of building materials. These sites were selected to provide diverse 
weather conditions and are located at the following facilities : 

NBS, Gaithersburg, Maryland 

Fort Holabird, Baltimore, Maryland 

U.S. Naval Station, Roosevelt Roads, Puerto Rico 

Nellis Air Force Base, Las Vegas, Nevada 

Fort Lewis, Tacoma, Washington 

Fort Greely, Fairbanks, Alaska 

Permanent racks for holding specimens are now in place and materials 
are being exposed at all sites. 

Many studies are underway to evaluate the effects of these various 
climates on materials. Some of the current studies are concerned with 
(1) weathering characteristics of aluminized steel and roofing, (2) the 
spalling resistance of porcelain enamels, (3) the color stability of 
plastics, and (4) the durability of paints. 

144 



A program will be implemented to obtain or measure the exposure 
parameters at the sites. Static sampling devices from the Public Health 
Service, designated as "Effects Packages", have been placed at the 
NBS (Gaithersburg) and Ft. Holabird (Baltimore) sites. These de- 
vices indicate air quality and in conjunction with weather data will 
help establish the relative severityo f exposure conditions at each site. 

Wind Effects on Buildings — The effects of wind on buildings is the 
subject of a study jointly sponsored by the Environmental Science 
Services Administration and NBS. This problem has assumed great 
importance with the recent trend toward lighter more slender build- 
ings and larger window panels. U.S. Weather Bureau records indicate 
the average yearly damage to structures by wind in the continental 
United States is approximately $600 million with two years on record 
for which the damage exceeded one billion dollars. The study will ulti- 
mately result in improved design techniques for structures exposed to 
wind. Most building codes make some provision for wind loads but are 
largely based upon results of wind-tunnel studies in which prototype 
conditions were incorrectly modeled. A number of pressure sensors 
have been installed in the Building Eesearch Building at the NBS 
site to measure both steady and fluctuating pressures over the exterior 
walls. Simultaneous recordings of the oncoming wind are obtained 
by means of fast-response anemometers on an array of six towers 
placed upwind of the building. Once the techniques associated with in- 
strumentation, data acquisition, and data reduction are perfected, the 
study will focus on taller buildings where the response of the structural 
frame to aerodynamic forces is of primary concern. 

Strength of Inserts Embedded in Reinforced Concrete Slabs — As 
the cost of construction continues to increase, more and more designers 
are looking for methods to optimize floor space utilization. One method 
commonly used is to suspend from the ceiling equipment which might 
otherwise be occupying premium floor space. An increasing number 
of devices suitable for suspending such loads are being used in indus- 
trial, institutional and commercial buildings. 

One such device being used with reinforced concrete slab construc- 
tion is an anchor commonly called a concrete insert. These concrete 
inserts are made to receive either an ordinary threaded rod or the 
head of a machine bolt. They are simply fastened to the f ormwork prior 
to placing the concrete. This simplicity offers advantages over other 
devices such as embedded anchor bolts which must penetrate the nor- 
mally reusable f ormwork. 

As far as is known, no systematic study of the factors which affect 
the load-carrying capacity of inserts in reinforced concrete slabs has 
been published. It is known that some manufacturers have investigated 
certain variables, but the scope and the results of the tests are not 
known. Ordinarily, the manufacturer's catalogs are the only source 
of data regarding the load-carrying capacity of most of these inserts. 

145 




To save floor space, equipment is often suspended from inserts embedded in 
concrete ceilings. A systematic study was made of the factors affecting the 
strength of these inserts. Here, an insert has been tested to failure in a sus- 
tained load test. 

Because of the limited availability of concrete insert data the Build- 
ing Research Division, in cooperation with the Post Office Department, 
conducted a comprehensve study of the variables influencing the ulti- 
mate load carrying capacity of some commonly used inserts. 

In the test, the effect of cyclic fatigue on the pull-out strength of 
the inserts was being investigated. 

In a report recently issued, design criteria for the inserts w r ere rec- 
ommended. These criteria take into consideration 10 variables com- 
monly encountered in construction. 

Study of Occupancy Loads in Postal Facilities — The Post Office 
Department is faced with the problem of moving an ever increasing 
volume of mail efficiently and rapidly from pickup to delivery. To 
cope with the problem, efforts are being directed toward mechanizing 
the mail handling and processing operations. This equipment accounts 
for a large portion of the occupancy load that is imposed on Post 
Office structures. It is expected that the loads on these facilities will 
increase as more and more automatic mail processing equipment is 
developed and installed in the buildings. Present data is inadequate 
for design of post office structures for the expected loadings over the 
useful life of the building. Consequently, the present design procedure 
must, of necessity, include exceedingly conservative values for 
loadings. 



146 



The Building Kesearch Division has undertaken a project to study 
the existing loads in a sample of postal mail handling facilities across 
the nation. The main objective is to investigate the magnitudes and 
distributions of actual occupancy loads imposed on the structures for 
the purpose of making engineering recommendations for values of 
loads to be used in the design of new facilities. 

The work has been in progress for approximately one year and was 
carried out in two phases. The initial phase of the work was to develop 
background information on mail handling operations, process machin- 
ery, and facility layouts, and to formulate the most suitable measure- 
ment techniques and evaluative methods for conducting the study. At 
the same time, load sensing devices and data acquisition instrumenta- 
tion for field measurements were designed and developed in the 
laboratory. 

The next phase of the work was concerned with the field survey of 
actual loads in specific structures selected as a representative sample of 
Post Office mail handling facilities across the nation. Computer pro- 
grams are being developed for automatic data processing and evalua- 
tion. Three facilities, located at Greensboro, N.C., Chicago, 111., and 
Buffalo, N.Y., have been surveyed thus far with plans to survey at 
least six more over the next year. 

Measuring the Smoke Generating Characteristics of Materials — 
The smoke density chamber, designed and developed at the Bureau, 
was put into commercial production following comparative testing 
and preparation of a formal proposal of method. The illustration 
shows the first commercially produced model. There are nine chambers 
in existence and 16 under delivery to testing laboratories and private 
corporations. 

The smoke density chamber method measures the smoke generating 
characteristics of solid materials by monitoring the attenuation of a 
light beam by the suspended particulate matter generated from mate- 
rials under both pyrolytic decomposition (smoldering) and flaming 
combustion within a closed chamber. The resulting measurement is 
expressed in terms of maximum specific optical density and the time 
to generate a specified fraction of the maximum specific optical density. 

Developmental testing with the smoke density chamber resulted in 
several design and technique improvements. These included: (1) a 
multihole burner for better flame anchoring and uniform distribution 
during flaming exposures, (2) techniques for supporting thermoplas- 
tic materials, and (3) a procedure for evaluating the influence of 
delamination, cracking, peeling or other separations on the smoke- 
generating characteristics of laminated or faced composite materials. 
National Conference of States on Building Codes and Standards — 
In fiscal year 1969, continued staff support was given to a number of 
States in organizing a National Conference of States on Building 

147 



; ? 




The smoke-generating characteristics of materials are studied in this smoke 
density chamber, which measures the attenuation of light resulting from the 
smoke generated by smoldering or flaming materials. 



Codes and Standards. Modeled after the National Conference on 
Weights and Measures, the objective is to obtain more uniform build- 
ing standards among the States. Since a majority of the States do not 
have research facilities, the National Bureau of Standards building 
technology program findings will serve in support of the States in the 
National Conference. 

The second annual meeting of this group was held in April 1969, 
attended by representatives from 36 states, the District of Columbia 
and Puerto Rico. Revised procedures and by-laws were adopted, stand- 
ing committees established, and the Conference unanimously approved 
the goal of achieving a greater degree of intrastate and interstate 
uniformity within and among the states in matters of building code 
requirements and standards. 

Floor-Surface Resistance to Movements of Wheeled Vehicles — The 
Public Health Service has been faced with an increasing demand for 

148 



use of different floor coverings, such as carpeting-, in hospital and 
other health care facilities. The National Bureau of Standards de- 
veloped a testing procedure to measure starting and rolling friction 
of wheeled vehicles on various floor surfaces. A hospital bed was se- 
lected as the test vehicle to be used in the study as it is the most prev- 
alent piece of portable equipment in the hospital. Instrumentation was 
devised to measure the forces required to initiate motion as well as to 
measure the forces required to maintain motion of the bed. Forces 
were measured with the bed empty and with an applied live load of 
300 pounds. Nine different floor coverings were tested while the test 
bed was equipped with casters designated by the manufacturer as 
"hard" and u soft.' ? Results show that soft coverings may offer almost 
five times as much resistance to movement as does resilient floor 
covering. 

Performance Teats of a Prefabricated Building — The structural and 
thermal performance of a prototype prefabricated building system 
was determined for the U.S. Navy. The building system is being de- 
veloped for use as an advanced-base, relocatable structure. The build- 
ing was made of modular sandwich panels. Floor, wall and roof panels 




Part of the equipment used in structural tests of a prefabricated building, one 
wall of which is seen at the far right. 



149 



consisted of interior and exterior aluminum skins bonded to a kraft 
paper-honeycomb core. The test building was prefabricated in Florida, 
trucked to 1STBS, and erected for test in the large Building Research 
Division environmental test chamber. 

Structural tests to simulate wind loads and snow loads were made. 
Air leakage at the windows and doors and at the joints of the pre- 
fabricated elements was measured with a small inside pressure and 
revealed by smoke tests. Heat loss and condensation observations were 
also made. 

As a result of the performance tests a number of design changes 
were recommended to improve the thermal and structural performance 
in the further development of this building system. 

Field Studies of Air-Cleaning Systems in Post Offices — In coopera- 
tion with the Post Office Department, the Bureau 's Building Research 
Division made measurements of the diurnal and seasonal variations of 
the airborne particulates in postal work spaces under operating con- 
ditions. The purpose of this work was to determine the performance 
of different types of filters and air-cleaning systems in use to help 
prescribe the most economical and effective ways for cleaning air. Air- 
borne dirt is not only important for health and housekeeping reasons, 
but it is also a possible cause of failure in mail-handling and processing 
machines. The field measurements involved application of techniques 
used for air pollution studies as well as several new techniques de- 
veloped specifically for building spaces and ventilating systems. 

Electronic Technology 

The electronics industry is one of the fastest growing and most 
heavily research-oriented in this country. In the context of R&D funds 
spent by the industry, NBS activities are relatively small, but the 
Bureau's influence is broad. Devices are being developed faster than 
adequate measurement methods for the control of the fabrication 
processes and for the characterization of the finished devices. The 
Bureau's contribution to the fields lies in this critical area. Its pro- 
gram emphasizes the development of improved basic measurement 
methods of significance to advances in the entire technology. 

Since the Government purchases more than half of the industry out- 
put, the Bureau's work is of interest to many Federal agencies. The 
Bureau has undertaken joint programs on methods of measurement 
for semiconductor materials, process control, electronic devices and 
transducers. The objectives of these programs are enhancement of the 
performance, interchangeability, and reliability of discrete semicon- 
ductor devices, integrated circuits, and transducers and improvement 
of their use through better methods of measurement specifying ma- 
terials and devices and in control of device fabrication processes. The 

150 



goal is to provide a set of measurement methods which have been care- 
fully evaluated for technical adequacy, which are acceptable to both 
users and suppliers, and which can provide a common basis for the 
purchase specifications of government agencies. At the end of the fiscal 
year investigations were underway in a large number of measure- 
ment areas in addition to activities related to technical and informa- 
tion services. 

InJwmogeneities — Variations in the resistivity of a silicon wafer 
can cause significant variations in device characteristics. In large 
scale integrated circuits and large area power devices these variations 
result in nonuniform current distributions which may be unnoticed 
until they cause device failure. Although it is possible to measure 
resistivity variations by means of a point-to-point measurement with 
conventional four-probe or spreading resistance techniques, a scanning 
technique is more suitable in many applications because it does not 
require the placement of probes on the region of interest. A study 
of photovoltaic method for measuring resistivity variations shows 
that this technique gives qualitative resistivity profiles on circular 
silicon wafers. Recent efforts have been directed toward the establish- 
ment of an analytical expression to relate the photovoltage measured 
on the diameter of a circular wafer to the resistivity gradient. The 
studies of various surface preparations have also led to the selection 
of a technique which reliably and consistently reduces the adverse 
effect of surface recombination in p-type silicon wafers. 

Deep-Lying Trapping Levels in Indium Antimonide — Semiconduct- 
ing compounds of the III-V type, such as indium antimonide, contain 
naturally occurring trapping centers located near the middle of the 
forbidden energy gap. These centers control the electrical properties 
of high-purity specimens from which most of the shallow doping 
impurities have been removed. Although observed in all reported 
specimens of high-purity indium antimonide, the origin of these 
centers remained uncertain. From results of NBS experiments in 
which electrical resistivity, Hall coefficient, and majority and minority 
carrier lifetimes in high-purity indium antimonide specimens were 
measured before and after the addition of lithium, the donor-like 
nature of the center was confirmed ; a simple lattice vacancy, probably 
an indium vacancy, appears to be responsible for the trapping center. 
The trapping centers are apparently frozen in at a concentration of 
approximately 10 14 cm -3 during crystal growth. Growth of crystals at 
lower temperatures, as, for example, by vapor deposition, would be 
expected to result in a lower concentration of vacancies. 

Wire-bond evaluation — A dominant cause of device failures in both 
radiation and nonradiation environments is failure of the wire bond 
used in connecting the semiconductor chip to the external leads. Most 
wire bonds are of good quality and do not fail. The problem is the 

151 



early identification of those which will eventually fail in use. Survey 
and evaluation of methods used for determining strength of wire bond 
systems in semiconductor devices have been undertaken. A compre- 
hensive study of existing procedures and techniques is nearing com- 
pletion and a critical review of the present status of wire bond testing- 
is being prepared. Systematic studies of factors which influence wire 
bond quality have been initiated in order to identify those parameters 
for which tests must be standardized. An improved method of grasping 
wire has been developed for use in pull tests which are commonly 
employed to determine the strength of the wire bond. 

Radiation. Damage in Silicon Nuclear Detectors — Silicon nuclear 
radiation detectors operating on earth-orbiting satellites and deep 
space probes can be destroyed by high fluxes of low-energy protons 
and electrons which exist in the trapped-radiation belts or which arise 
from transient solar events. In cooperation with the NASA-Goddard 
Space Flight Center, the Bureau's Electronic Technology Division 
has been studying radiation damage effects in silicon surface-barrier 
transmission detectors so that the useful lifetime of such satellite- 
borne detectors can be predicted. Effects of damage by protons with 
energies between 50 keV and 5.0 MeV have been studied; damage 
from electrons with energies between 100 keV and 2.0 MeV is cur- 
rently being investigated. The study has shown that general guidelines 
for reducing the effects of damage by low-energy charged particles 
include (1) the operation of detectors at the highest fields possible, 
and (2) a reduction of the density of defects produced by radiation 
in the high field or barrier region of the detector. With respect to the 
latter point, the useful lifetime of silicon transmission detectors operat- 
ing in the presence of low-energy protons was found to be extended 
several orders of magnitude when the detector was mounted so that 
the rear, ohmic contact was irradiated rather than the front, surface- 
barrier contact. 

Thermal Management — Power dissipation in a semiconductor device 
is limited by the maximum permissible temperature of the semicon- 
ductor junction. To assist users in determining junction temperature 
under actual operating conditions, semiconductor manufacturers spec- 
ify the thermal resistance and in some cases the transient thermal 
response of the device. These are determined indirectly by means of 
electrical measurements, or calculated from heat transfer considera- 
tions. In either case, accuracy and reproducibility are poor, and ade- 
quate correlation between calculated and measured values and between 
values obtained by different methods of measurement is lacking. 
Much of this difficulty results from the fact that the current distribu- 
tion is usually not uniform over the area of the junction, causing 
localized variations in junction temperature and further discrepancy 
between the predicted junction temperature and the actual value at 

152 



the highest, and therefore most critical, local temperature. The seri- 
ousness of this problem has been repeatedly emphasized by suppliers 
and users of semiconductor devices, individually and through the 
Electronic Industries Association. 

In response to these needs, a critical review of thermal resistance 
and thermal response measurements in diodes and transistors has been 
undertaken. The validity and reproducibility of existing methods of 
determining thermal resistance is being studied in the laboratory. 
Thermographic phosphors are being used to determine the relationship 
between the junction temperature predicted by the methods and the 
actual junction temperature in the device. A study to determine the 
feasibility of using temperature-sensitive phosphors to measure the 
temperature distribution on the surface of a transistor chip has been 
completed and equipment assembled to facilitate the use of such phos- 
phors for this purpose. Better understanding of the thermal per- 
formance of semiconductor devices will permit better prediction of 
their power-handling capabilities under both continuous and pulse 
operation and will enhance efforts to detect anomalies by screening 
for abnormal heat dissipation. 

Characterization of Germanium for Nuclear Radiation Detector* — 
A comprehensive program for measurement of the characterization 
of materials and quality of gamma-ray detectors fabricated from test 
specimens of germanium submitted for analysis is being carried out in 
cooperation with the Atomic Energy Commission. 

Presently 68 germanium crystals contributed by various domestic 
and foreign suppliers, and U.S. and Canadian national laboratories 
and universities are being evaluated. The correlation of three methods 
for determining oxygen in germanium — infrared absorption, lithium 
precipitation and lithium mobility — is being studied. Lithium ion 
drift-mobility in germanium has been measured between 24 and 61 °C, 
the temperature range normally encountered in the fabrication of 
lithium-drifted germanium gamma-ray detectors. The values meas- 
ured were higher than those previously obtained by extrapolation 
from data obtained above 150 °C. Based on these studies, a method 
for evaluating germanium crystals by determining the mobility of 
lithium has been developed for the American Society for Testing and 
Materials Committee F-l. 

Piezoelectric Response of Polymers — Piezoelectric materials are 
used in a wide range of applications to generate and to measure motion, 
pressure, and flow. In many cases their applicability or their efficiency 
is limited because presently used piezoelectric materials are hard, stiff, 
dense, and brittle. Polymers provide a choice of mechanical properties 
ranging from those of light, soft, foam rubber to some approaching 
those of crystalline materials. However, the piezoelectric response of 
available polymers, when it exists, is too small for practical applica- 

153 



tions. NBS investigation shows that proper treatment with heat and 
intense electric fields could develop a piezoelectric response in some 
inactive polymers and significantly increase the response in polymers 
having slight activity. The results of the investigation suggest that 
improved methods of treatment could develop sufficient piezoelectric 
response in polymers for technological and industrial applications. 

Systems Analysis 

In any program for promoting the application of technology to com- 
plex problems of industry or Government, the use of systems analysis 
or operations research is almost a mandatory requirement. The NBS 
Technical Analysis Division (TAD) seeks to develop, test, and dis- 
seminate systems analysis techniques which are applicable to public 
sector problems in terms of program planning, resource allocation, 
and program execution. 

The IAT systems analysis group is the largest such organization 
within the civilian agencies of the Government. It serves other agencies 
in the solution of their specific systems analysis problems, and helps 
these agencies to develop their own capacity to tackle complex systems 
problems. It also conducts research on the cost-benefit analyses for 
Government programs. 

During FY 1969 the IAT systems analysis group started a modest re- 
search effort in standard definitions for the concepts and elements 
used in the economic evaluation of Government programs, particularly 
in the area of applied science projects. Methods were proposed for 
measuring the economic value of Government services to individual 
citizens in contrast to services for business or public agencies. 

Post Office Department Mechanization Projects — A systems engi- 
neering project is currently being conducted to develop specifications 
for mail-handling systems. These specifications may be used by the 
Post Office Department Bureau of Research and Engineering as a guide 
in developing more efficient and effective hardware. 

A parallel study identifies and quantifies the relationships between 
physical characteristics of letter-sized mail and mechanical mail proc- 
essing. This study will define the limits of mechanical processing. 

A research program at the Human Factors Laboratory of the Bureau 
of Research and Engineering is directed and staffed by NBS person- 
nel from TAD's Behavorial Sciences Group. Research projects in- 
clude identification of the man-machine aspects of postal mechaniza- 
tion. Recent studies have included evaluation of closed circuit televi- 
sion as a means of viewing the addresses on letter-sized mail ; examina- 
tion of the relationship of the number of digits in a numeric code to 
the processing time for a piece of mail ; and a comparison of machine 
pacing and self-pacing in the operation of tAvo configurations on 
numeric keyboards. 

154 



Maritime Consolidation Centers — In response to the U.S. Maritime 
Administration, the Bureau investigated the advantages of strategi- 
cally locating centers where goods for export and import could be con- 
solidated and loaded in containers. Such centers would be established 
at intermediate points between importers or exporters of commodities. 
Cargo would accrue until a full container could be shipped. 

The Division analysts have developed a model for evaluating the 
costs and benefits which the shipping industry would derive from the 
establishment of such centers. It was found that the specific location of 
points where goods could accumulate and be containerized would be 
of definite advantage to the shipping industry and the U.S. Merchant 
Marine. 

Progress in Transportation Simulation Studies — The Northeast 
Corridor Transportation Project sponsored by the Department of 
Transportation has advanced to an operational stage in which the 
complex of models has been used to evaluate a set of alternative trans- 
portation systems for the Northeast Corridor. A variety of new trans- 
portation technologies — high-speed rail, tracked air cushion vehicles, 
vertical takeoff aircraft and the like — have been examined using the 
models. The result of the simulation tests are undergoing review and 
will be used to make suggestions as to choosing among possible Federal 
government policies with regard to the development and implementa- 
tion of intercity transportation facilities. 

The Department of Housing and Urban Development asked the 
NBS Technical Analysis group to develop the necessary concepts for 
adaptation of the Northeast Corridor Transportation models for use 
as urban transportation analysis tools. Some of these concepts were 
directly applicable to the intraurban transportation scene. Three sub- 
models were developed for experimental purposes. 

Coast Guard Operations — In response to a Coast Guard request a 
data base was constructed for analyzing the search and rescue opera- 
tions of Coast Guard units throughout the country. A computer pro- 
gram was developed to edit raw data tapes provided by the Coast 
Guard, reformat records of operations, sort reported cases by district 
and operating facility and print summary statistics. The Coast Guard 
is using the outputs for each of several years to evaluate hypotheses 
concerning the activities of its shore stations. 

A second project underway is the construction and exercising 
of a simulation model for a research and rescue force integration 
analysis. 

Urban Studies Projects — The Technical Analysis Division em- 
barked on a cooperative project with the International City Managers' 
Association, Fels Institute of the University of Pennsylvania and the 
Department of Housing and Urban Development to determine the 
applicability of systems analysis and operations research techniques 
to the resolutions of urban problems. 

375-572—70 11 155 



Numerous cities throughout the country have begun to apply systems 
techniques to the resolution of varying types of urban problems. Staff 
members have recently been involved in an effort to evaluate the state- 
of-the-art. A forthcoming publication will cite the cities using the 
systems methods and the problems to which they have been applied. 
The publication will serve as an important source document for gov- 
ernment agencies, city staffs, consulting firms and universities active 
in the area of urban problems. 

During FY 1969, the Division acted as "technical coach" to the 
city staff of East Lansing, Michigan. A model was constructed which 
enabled the city staff to determine the optimal number and location 
of fire stations necessary to protect the city now and in the future. 

In cooperation with the Montgomery County School Planning 
Board, Maryland, a model was built to determine an optimal school 
districting plan. The model was applied to the elementary schools in 
the Takoma Park area. An operational computer code of a transporta- 
tion algorithm was modified to meet the districting criteria of the 
Planning Board. This methodology reduces the time required to 
establish these districts. 

Motor Vehicle Safety 

During fiscal year 1969 the Office of Vehicle Systems Kesearch in 
the National Bureau of Standards continued its research activities in 
tire systems, occupant restraint systems, braking systems, and vehicle 
structures. This work is sponsored by the National Highway Safety 
Board of the Department of Transportation in order to provide the 
technical basis for motor vehicle safety performance standards. 

Tire Systems — A major activity of the tire research program was 
concerned with developing a uniform quality grading system for motor 
vehicle tires to enable consumers to make an informed choice in the 
selection of tires. The tasks involve establishing (1) standard methods 
of test for the several properties required to evaluate tire quality; (2) 
quality levels for each property; and (3) a means of conveying the 
information to the consumer. For this system a method for rating the 
relative tread wear has been developed. It requires the inclusion of 
various pavements surfaces, prescribed amounts of cornering, braking, 
and acceleration. The tests are designed so that effects of wheel posi- 
tion, vehicle, and weather can be estimated and removed from 
consideration in the evaluation scheme. 

In progress is work to establish wet traction standards for tires, 
standards for resistance to impact damage, and methods for 
nondestructive examination of tires. 

Occupant-Restraint Systems — Included in the second series of sled 
tests at the Holloman Air Force Base were experiments involving 
human volunteer subjects riding on automotive production seats and 

156 



restraint-simulating crash levels up to 14 g. The kinematic trajectory 
of these subjects has been plotted from the high speed motion picture 
coverage. Computer analysis of the data from these tests is producing 
data on velocity and movement of various body members, seat belt 
and shoulder harness loading, leg, and muscular reaction, etc. 

New laboratory procedures are being developed for static and 
dynamic sled testing of restraint systems. A test method has been 
developed for determining the degree of resistance to lateral intrusion 
of various vehicle door systems. 

Braking Systems — Road test procedures and instrumentation are 
being developed to measure the safety performance of a braking sys- 
tem and its components. To establish correlation between road tests 
and laboratory tests, research programs have included the utilization 
of a special purpose double-ended inertia dynamometer, a friction ma- 
terials test machine, friction assessment screening test machine 
(FAST), and a "scale" machine from England. One of the objectives 
of this effort is to develop laboratory methods for safety performance 
standards for replacement brake linings. 

Recommendations were made to the National Highway Safety Bu- 
reau for upgrading the brake fluid regulations with respect to actual 
performance requirements and packaging and labeling of fluids. Un- 




Instrumented test vehicle used for evaluation of braking systems under normal 
and various types of failure conditions. 

157 



der development has been a humidity exposure test procedure to 
establish percent water pickup by the fluid after one to two years 
service. Testing facilities for automotive flexible brake hoses are 
nearing completion. 

Engineering Materials 

IAT provides advisory, consultative, and laboratory investigation 
services relating to selected engineering materials. The laboratory 
work is mainly for the development of test procedures which can be 
used by other testing laboratories. The staff responsible for this pro- 
gram works with national and international groups to establish stand- 
ards for these materials. Services also include establishing a technical 
base for other Government agencies to set purchase specifications. 

Magnetic Tapes for Satellite Recorders — The early failure of 
NASA flight recorders is one of the most important causes of satellite 
failures. New satellite designs calling for performance for several 
years, rather than a few months, magnify the problem. NBS has con- 
tinued its study of the changes of physical and chemical characteristics 
of magnetic tapes during their use. The interactions of tape and head 
surfaces are of special concern. Tapes are operated over dummy heads 
of known composition, with controlled parameters of atmosphere, 
temperature, tape tension, and tape speed. Changes in such properties 
as stiffness, hardness, surface roughness, coefficient of friction, and 
wetting characteristics are measured. Detection and identification of 
material that deposits on heads is carried out by contact angle measure- 
ments, interference microscopy, and infrared spectroscopy. 

Experimental tapes, expected to have improved stability, have been 
produced in this laboratory. These tapes are based on polyimide resins 
and have improved friction and hardness properties as well as high 
resistance to heat, chemicals, and radiation. 

Textile Evaluation by the Apparel Industry — A cooperative pro- 
gram conducted with The Apparel Eesearch Foundation resulted in 
a book, "Testing Programs for the Apparel Industry — Evaluation of 
Materials and Components," and a series of training programs based 
on the book. This work was based on a survey of the industry. The 
booklet describes three types of textile testing programs, testing 
equipment, its intended use, and approximate price. Test methods 
described include those of ASTM, AATCC, and the Federal Govern- 
ment. The training programs presented were fully subscribed and 
others are planned. 

Plastics Technology — An example of effective consultative and 
advisory service is a problem undertaken for the U.S. Navy. The Navy 
experienced difficulty in specifying and obtained a very heavy intri- 
cate polypropylene part that would meet difficult performance require- 

158 



ments. This item is a major component of a new weapons system. NBS 
was able to obtain satisfactory parts, by means of a relatively new 
forming technique, that had both improved design and mechanical 
properties. At the same time the cost of these items was reduced from 
approximately $450 each to about one dollar. 

Collaborative Reference Program for Paper — Accurate paper test- 
ing procedures are of major concern to the pulp and paper industry. 
Because of the large volume of production, even small systematic 
errors in test values can be very costly. A collaborative reference pro- 
gram, administered by the Bureau at the request of the Technical 
Association of the Pulp and Paper Industry (TAPPI), provides a 
mechanism for participating laboratories periodically to check the 
level and uniformity of their testing in comparison with that of other 
laboratories. Test samples are distributed bimonthly to the partici- 
pants and the results of the test determinations are returned to the 
Bureau for an analysis of the data. Reports, in which the laboratories 
are identified only by code number, are prepared bimonthly and 
include test results, averages, and standard deviations for individual 
laboratories and for the group as a whole. The first shipment of samples 
under the program was made in March 1969 to over 100 participating 
laboratories. 

Thermal Stability of Modified Celluloses — Differential thermal 
analysis (DTA) and thermogravimetric analysis (TGA) are useful 
tools for studying thermal stability, phase transitions and changes in 
structure of materials. These techniques have been used to obtain in- 
formation on the effects of modifying cellulose through reaction with 
specific oxidizing agents to produce varying amounts of aldehyde, 
carboxyl and ketone. The nature of the carboxylic acid salt, especially 
calcium and aluminum salts, is of interest in relation to papr mill 
practice. Aluminum sulfate is widely used in papermaking, and 
calcium carbonate is sometimes used as a filler. 

Cellulose normally shows a massive DTA endotherm at about 350 °C. 
The temperature of this endotherm usually is lowered by modifications 
made through oxidation, and by covering the carboxyls with aluminum. 
The temperature of this endotherm is raised if the carboxyls are con- 
verted to calcium salts. Thus, aluminum tends to unstabilize cellulose 
and calcium tends to stabilize it. 

Aluminum sulfate that is incorporated into paper during the paper- 
making process is thought to contribute to instability because of 
hydrolysis, producing sulfuric acid. Both DTA and TGA data indicate 
that the effects of alum and of sulfuric acid are quite different. At the 
same time, it appears that cross-linking occurs in each case. 

Flammable Fabrics — Various combinations of ignition, heat trans- 
fer, flame spread, and the liberation of toxic or irritant products of 
combustion represent the hazardous characteristics of flammable 

159 



fabrics and related materials. Research was initiated on the relation- 
ships between these fundamental characteristics and with hazards to 
life and property. In response to notices by the Department of Com- 
merce that there may be need for new or amended flammability stand- 
ards for wearing apparel, carpets, and rugs, several test methods are 
under development or evaluation as proposed standards. The notices 
were based in part on flammability test data obtained and analyzed 
by NBS on garments recovered by the Department of Health, Educa- 
tion, and Welfare from burn cases. NBS technical experts are co- 
operating with the Department of Health, Education, and Welfare in 
the design of better data gathering programs. NBS sponsored a two- 
day symposium on the measurement of flammability. The symposium 
was attended by over 500 representatives of industry, the academic 
world, and government agencies. 

Engineering Standards 

Standards Information — In fiscal year 1969, the Bureau, through its 
Office of Engineering Standards Services took a step toward improv- 
ing communication among the nation's standards-writing groups by 
announcing the availability of information on engineering and related 
standards and specifications. During the past year, 1,178 standards 
were added to the collection, bringing the total to 19,000 from 353 U.S. 
trade, professional, and technical societies. A Key-Word-In-Context 
(KWIC) Index was compiled, which lists the standards alphabetically 
by key words in their titles and gives the number and sponsoring 
group for each standard. This Index will aid individuals in deter- 
mining if there is a standard (or standards) in their areas of interest 
and in locating groups that could answer their questions on specific 
standards. Standards-writing groups will be able to use the Index 
before they initiate a standards project to determine if there is an 
existing standard covering the same subject. A need for this type of 
information is evidenced by the 900 inquiries concerning the KWIC 
Index which were received between January 1969 and the end of the 
fiscal year. About 5,600 inquiries regarding standards and stand- 
ardization activities were received in fiscal year 1969. 

Product Standards — One standard and two amendments were pub- 
lished, five other recommended standards were approved for publica- 
tion, and 14 were circulated to industry for determination of their 
acceptability. Additionally, four proposed standards were circulated 
for comment and 29 standards were transmitted for committee ap- 
proval. Reviews of 312 existing standards were in progress and recom- 
mendations for withdrawal, revision or revalidation were made on 
29 standards. 

Consumer Standards — Progress was made on several programs of 
interest to consumers in fiscal year 1969. A voluntary standard for salt 

160 



packages was approved for publication and four other consumer com- 
modity packaging standards were initiated. These proposed standards 
cover toothpaste, instant nonfat milk, instant mashed potatoes, and 
green olives. 

Another area of consumer interest concerns standards which estab- 
lish size classifications, according to significant body measurements, 
for patterns and apparel. In this area, revisions of the "Women's" 
and "Boys' " standards were formally initiated ; under development 
were a revision of the "Girls' " standard, and a new standard for male 
"Students," and a "How to Measure" standard. 

Fair Packaging and Labeling — The National Bureau of Standards 
has continued to pursue the implementation of the responsibilities 
assigned to the Secretary of Commerce under the Fair Packaging and 
Labeling Act. With cooperation by producers, distributors, and 
weights and measures officials from the states, counties, and cities, 
voluntary decisions have been reached covering a significant portion 
of the packages subject to the statute. Evidence of industry action in 
this area can be seen in the tabulation below and also in the 
marketplace. 

Percent Reduction in Package Sizes by Commodity 
[Achieved by agreement as of July 1969] 



Product 



Percent 
reduction 



Adhesive bandages 73 

Dry breakfast cereal 52 

Cheese 36 

Cookies and crackers 23 

Dry detergents 75 

Instant coffee 20 

Instant tea 67 

Jellies and preserves 37 

Macaroni products 50 

Mayonnaise and salad 

dressing 20 

Paper napkin 28 



Product 



Percent 
reduction 



Paper towels 76 

Peanut butter 60 

Pickles * 35 

Potato chips * 33 

Refrigerated dough 

products * 24 

Salad and cooking oils 53 

Soft drinks * 33 

Syrups * 20 

Tea bags 33 

Toilet tissue (1 ply) 20 

Toilet tissue (2 ply) 36 



* Estimated. 

New State Standards — During fiscal year 1969, seven additional 
States received new State standards. The seven included Georgia, 
Hawaii, Kentucky, Missouri, North Carolina, Pennsylvania, and Wis- 
consin. To date, the Bureau, under this program, has provided new 
equipment to 30 States. Manufacture of additional sets of precise 
physical standards and instruments is continuing and the ultimate 
goal is to update all State weights and measures laboratories. 

Basic laboratory training (two weeks) has been given to 23 State 
metrologists at various State laboratories. 



161 



Technical Training — The demand for weights and measures train- 
ing continues to increase. This past year 31 training schools were held, 
an increase of five over the previous year. These schools were con- 
ducted throughout the country and at the NRS weights and measures 
laboratory. Training included basic laboratory techniques, advanced 
courses, and special purpose field work. In addition to techniques used 
in the laboratory, the courses cover items such as the effect of the 
Fair Packaging and Labeling Act on State and local enforcement 
policies of the weights and measures groups ; field testing operations ; 
and special training for foreign visitors, Federal agencies, and private 
industry. 

National Conference on Weights and Measures — The 54th National 
Conference on Weights and Measures was held in Washington during 
June. Major revisions, based on the past year's experience, were made 
in the Model State Packaging and Labeling Regulation. These 
changes were made to clarify requirements of the States with respect 
to consumer package quantity labeling, and to assure the consistency 
of the Model regulation with Federal requirements under terms of 
the Fair Packaging and Labeling Act, 

The Conference updated Handbook 44 "Specifications, Tolerances, 
and other Technical Requirements for Commercial Weighing and 
Measuring Devices." 

Standards Engineering — The engineering staff of the Office of 
Weights and Measures identifies, analyzes, and solves technical prob- 
lems in the measurement area of commerce. During the past year, they 
have studied and reported on such diverse subjects as wire and cordage 
measuring devices, a new method of calibrating rental car odometers 
and taximeters, and propane vapor meters. The vapor meter project 
resulted in the adoption of a new tentative code in NRS Handbook 44, 
the basic working reference used by weights and measures officials 
throughout the country. A study to help local weights and measures 
officials calibrate grain moisture meters has been initiated. 

Two new publications concerned with important areas of Standards 
and Engineering were distributed during '69 ; NBS Handbook 105-1, 
Specifications and Tolerances for Field Standard Weights, the first in 
a series, and an unpublished report. 

TECHNICAL SUPPORT ACTIVITIES 

The Institute for Applied Technology (I AT) — Provides engineer- 
ing and development assistance in applying measurement technology 
to specific measurement problems. These services are used by other 
research programs in the Rureau, and by other Federal agencies. Work 
of this nature involves electronic techniques or combinations of elec- 
tronics with mechanical, thermal or optical methods. It also includes 
the production of instrument prototypes. Examples of the services 
follow. 

162 



Performance of AG-to-DG Voltage Transfer Standards — A recently 
completed standard is based on comparing the average of a rectified 
alternating voltage with a direct voltage, the principle inherently used 
by a majority of present-day AC voltmeters. With this standard, a 
comparison accuracy of 20 ppm (parts per million) was obtained at 
audio frequency, increasing to 200 ppm at 100 kHz. This work com- 
plements the earlier development of an AC-DC transfer standard 
based on comparing the peak value of the alternating voltage with a 
standard direct voltage. 

Laser Emissions — In the field of length metrology, there is much 
interest in using particular laser emissions as intermediate length 
standards. Such use requires that the laser emission be calibrated 
against a primary standard wavelength, a process that is tedious and 
time-consuming when clone manually. Work continued on a scanning 
Fabry-Perot interferometer for comparing two light emissions, the 
goal being to allow laser wavelength calibrations to be made quickly 
and automatically. 

Comparing Circular Grooves — A precise gaging method for measur- 
ing and comparing circular grooves used to aline the electrodes of pre- 
cision capacitors. This instrument, which is not a jog or fixture, can 
also be used to measure precisely the diameter of circles as well as cir- 
cular grooves. The importance of this instrument is reflected in the 
requirements of the laboratory to align circular vee grooves to an 
accuracy of + 0.0001 of an inch or less. 

TECHNOLOGICAL INNOVATION AND DIFFUSION 

Technological innovation may be defined as that process whereby 
means are devised and applied for stimulating new technologies, 
channeling them in promising useful directions, and exploiting their 
use for purposes other than those for which they were originally 
developed. Technological diffusion, in the context of IAT programs, 
is largely restricted to disseminating the results of Government spon- 
sored K&D. 

Invention and Innovation 

The Office of Invention and Innovation is the IAT activity which 
helps to develop an environment conducive to technological change. 
Its basic program has three aspects: providing a national basis for 
formulation of climate-setting Federal policies, offering assistance to 
inventors, and education. 

In FY 1968, the Office assumed responsibility (as assigned by the 
Assistant Secretary of Commerce for Science and Technology) for the 
program, planning and budgeting activity of the Department of Com- 
merce Technology Program. Department programs included in this 
responsibility are the Patent Office, Office of State Technical Services, 

163 



the NBS Clearinghouse for Federal Scientific and Technical Informa- 
tion and the Office itself. 

Organization of American /States — At the request of the Director 
of the National Bureau of Standards, the Office conferred with a 
Working Group of the Organization of American States to devise a 
strategy for the technological development of Latin America. The 
recommendations of the Working Group were considered at the 1969 
Trinidad meeting of the OAS Cultural Council. 

Invention Programs — Twenty-four states held invention expositions 
and inventors' seminars during fiscal 1969 and several other states are 
planning to join this effort. The programs are organized and con- 
ducted by state organizations and universities and are aimed at facili- 
tating the licensing, development, and exploitation of inventions. NBS 
provides assistance in planning and undertaking the expositions and 
also provides experts for the seminar programs. 

Invention Policy — The Office of Invention and Innovation, in co- 
operation with the National Inventors Council, embarked on a policy 
study to determine the role of the Department of Commerce in encour- 
aging and providing assistance to independent inventors and inventor- 
entrepreneurs. The study will analyze the problems faced by inventors 
and inventor-entrepreneurs who seek to bring their inventions to frui- 
tion, describe present programs and mechanisms for aiding them, 
identify deficiencies in these methods of assistance, and explore alter- 
native ways in which the Department of Commerce and other agencies 
could properly help to overcome these deficiencies. 

Education for Innovation — A study of the role of the Department 
of Commerce in the education of prospective inventors, innovators and 
entrepreneurs is being conducted in cooperation with the National 
Inventors Council and the American Society for Engineering Educa- 
tion. It is a sequel to the 1965 National Conference on Creative Engi- 
neering Education, which was organized by the Commerce Depart- 
ment. The study will determine what has been done to promote creative 
education since the Conference and what needs and opportunities 
now exist with respect to the education of prospective inventors, inno- 
vators and entrepreneurs. The study will provide the basis for a report 
by the National Inventors Council to the Secretary of Commerce. 

Innovation Studies — An analysis of policies to promote technologi- 
cal innovation is being performed in conjunction with the George 
Washington University Program of Policy Studies. This study stems 
from two earlier events — one, the report to the Secretary on "Tech- 
nological Innovation: Its Environment and Management," and the 
other, an agreement by NBS with the Arms Control and Disarma- 
ment Agency to assist them in the formulation of policies that would 
ease the impact of a substantial cut-back in defense spending on high- 
technology enterprise and put to salutary use the resources thereby 

164 



released. Among the aims of the study are the development of a de- 
scriptive model of the processes by which technology is created, applied 
and diffused ; an evaluation of specific federal programs and policies 
that could or do influence these processes ; the development for com- 
parative analysis of innovation profiles of selected defense and civilian 
industries ; and the identification of key leverage points in the model 
where policies may be beneficially applied. 



165 



CENTER FOR RADIATION RESEARCH 

The Center for Radiation Research (CRR) develops improved tech- 
niques and instruments for detecting and measuring ionizing radia- 
tion, obtains basic data on the interactions of radiation with matter, 
and investigates the structure of the various forms of matter. The 
center also maintains radiation sources and standards for providing 
national services essential to industrial, medical, and research appli- 
cations. Radiation of concern to the Center is that with energies be- 
tween approximately 5 keV and 300 MeV, produced by radionuclides, 
reactors, and particle accelerators. 

Because of its unique facilities and competences, the Center not only 
has responsibility for carrying out the NBS mission in the area of 
radiation, but also for making its resources and capabilities available 
to other Government agencies, industry, and universities. This policy 
of facility sharing ensures efficient utilization of large multipurpose 
facilities, such as the reactor and linear accelerator, by making them 
available to a broad segment of the scientific community. A number of 
collaborative programs are now functioning successfully, in which 
university and Center scientists are jointly performing experiments of 
mutual interest. Approximately one-half of all the guest workers cur- 
rently at NBS are working in the Center. 

Although the programs of the CRR are complex and diverse, they 
can be grouped roughly as follows : 

1. Radiation Measurement and Standards 

2. Nuclear Physics Research 

3. Radiation Theory 

4. Structure of Materials 

5. Facilities Operations 

6. Technical Assistance to Others 

The experimental research effort is supported by a broad theoretical 
effort aimed at interpretation and analysis of the results. 

Radiation Measurement and Standards 

C alorimetrie Dosimetry by Means of Refvactometry — An interfer- 
ometer has been designed and constructed for measuring small changes 
in refractive index. In a transparent medium, the refractive index will 

167 



change due to a temperature rise resulting from radiation energy 
deposition. The interferometer, functioning as a refractometric calori- 
meter, is capable of measuring doses from 1 kilorad to 5 megarads at 
dose rates from 200 rad/s to 5 megarad/s. Measurements can be made, 
without the need for cables or heat-sensing probes, in any transparent 
medium for which the temperature -dependence of the index is known 
or can be determined. It is possible to make a speetrophotometric anal- 
ysis of the irradiated sample simultaneously with the interferometric 
measurements. 

Energy Deposition oy Electrons in Aluminum — Energy-absorbed 
distributions at various depths in aluminum have been measured with 
silicon detectors for normally incident monoenergetic electrons with 
energies of 0.5, 0.75, and 1.0 MeV. Pulse-height distributions were 
recorded from silicon (Z=14) transmission detectors with thicknesses 
of about 100 and 200 /xm at depth intervals of about 200 /mi in alumi- 
num (Z = 13). From a knowledge of the response of the detectors, the 
pulse-height distributions were converted to energy-absorbed distri- 
butions. The data yield both (1) the probability per incident electron 
that a specific amount of energy will be deposited in a given layer and 
(2 ) the total energy deposited in a given layer of aluminum. 

X- and Gamma-Ray Instrument and Source Calibrations — Fifty- 
six conventional roentgen meters with 200 condenser ionization cham- 
bers were calibrated in exposure units at various energies. Instruments 
capable of higher precision in exposure measurement are being sub- 
mitted in greater numbers, with 20 such devices having been cali- 
brated. In addition, the x- and gamma-ray facilities have been used 
for standard exposures to various kinds of thermoluminescence 
dosimeters. 

Twenty-one small gamma-ray sources were calibrated in exposure 
units, including live cesium- 137 sources. The capability for calibra- 
tions of small cesium- 137 sources was only recently established. 

A program has been drawn up for automating and computerizing 
the exposure-calibration facilities. Part of the equipment for auto- 
matic handling has been constructed in Bureau shops, and contracts 
have been awarded for additional items, including data- acquisition 
equipment. 

Thermoluminescence Dosimetry — Work was completed on a com- 
parison of the thermoluminescence (TL) sensitivity of LiF and 
CaF 2 : Mn for 60 Co gamma rays and 15-MeV electrons ; no difference 
was found in the sensitivity of these materials exposed to the two types 
of radiation. The measurements of TL response of CaF 2 : Mn irradiated 
in a CaF 2 medium to electrons between 1 and 4 MeV were not repro- 
ducible, possibly because the response was influenced by a nonrepro- 
ducible electron-charge distribution in the (insulating) CaF 2 medium. 
Work on this problem is continuing. 

168 



A search for a possible dependence of F- center formation in LiF 
on the gamma-ray exposure rate turned out negative for rates between 
about 1.5 X10 3 and 5X10 6 R/h. This result is compatible with the 
dominant role given ^-centers in some of the current models for the 
thermoluminescence process in LiF of TLD grade. 

Dose Distributions Measured with Radiochromic Dyes — Thin foils 
of approximately 1 mg/cm 2 containing stabilized dye precursors have 
been used successfully to measure gamma-ray and charged-particle 
energy deposition in extended media. The production of dye by irradi- 
ation is measured spectrophotometrically in terms of increase in optical 
density. The response does not vary appreciably over wide ranges of 
radiation energy and intensity. Experimental measurements of energy 
deposition as a function of depth of penetration of high-energy elec- 
trons and protons in various substances have shown reasonably good 
agreement with theoretical Monte Carlo calculations. Energy deposi- 
tion in inhomogeneous media irradiated with gamma rays has also 
been measured with high resolution, using the thin-dye systems placed 
across interfaces of different materials. 

Monitoring of High-Energy Electron Beams — The development of 
nonintercepting beam monitors employing ferrite toroids as pulse 
transformers has been refined to permit measurement of high -energy 
pulsed beams with an accuracy of the order of 0.1 percent for pulsed 
current well below 1 mA. The absolute accuracy of our high-energy, 




¥ : 



The color density of a radiochromic dye film is measured after electron irradia- 
tion. Density variations indicate changes in the dose distribution of the 
electron beam. 



169 



high-beam-power Faraday Cup is being studied by using the noninter- 
cepting monitor to measure directly the difference between beam cur- 
rent and current collected by the Cup. These differences can be repro- 
ducibly measured to within a feAV hundredths of a percent of the total 
current. Differences of a few tenths of a percent due to secondary elec- 
trons produced in the vacuum window of the Cup and back-scattered 
electrons are observed and are being investigated. 

Reactor Flux and Poiver Measurement — The neutron flux and 
power distribution in the NBS reactor were determined using new 
techniques developed at the Bureau as well as more standard methods. 
The usual thermal flux measurement technique of activating cobalt 
wires was supplemented by the activation of tungsten wires which 
were used to determine the epithermal flux by comparison to the cobalt 
measurements. The absolute value of the neutron flux was determined 
by activating a cobalt- 10 B glass bead. The relative power distribution 
was also determined independently by gamma-scanning each fuel ele- 
ment individually in a reproducible geometry. The power distribution 
determined in this way agreed with that from the flux measurements 
within a few percent, demonstrating the feasibility of the gamma-scan- 
ning technique. 

Neutron Cross Sections — The total neutron cross sections of hydro- 
gen, aluminum, calcium, titanium, iron, and nickel were measured in 
the neutron energy range 0.5 to 15 MeV. The neutron time-of -flight 
method was employed, with the NBS electron linear accelerator used as 
the pulsed neutron source. The energy resolution varied from 0.2 per 
cent to 0.9 percent ; both the statistical precision and the normalization 
accuracy were better than 2 percent. The hydrogen cross section was 
measured in order to check a recent suggestion that this cross section 
may not be smooth, but may have some structure. Our measurements 
showed that the cross section was, indeed, smooth. The rest of the 
elements measured are important constituents of shielding or construc- 
tion materials, and the measurements were made primarily for the 
purpose of providing data to be used in transport calculations. 

Chemical Dosimetry — A study has been completed on the system- 
atic errors which may be introduced in the spectrophotometric deter- 
mination of ferric ion concentration by incorrect evaluation of a non- 
linear calibration curve of the spectrophotometer. Several methods 
have been developed for using correctly a nonlinear relationship be- 
tween absorbence and molarity, in calculation of absorbed dose. 

Radioactivity Standards — A total of 341 radioactivity standards 
were sold in fiscal year 1969. Fifty-one source calibrations were made : 
41 for other agencies and companies and 10 for NBS laboratories. Fif- 
teen series of standards were produced totalling 1359 units, five of these 
series were prepared for use with Ge(Li) detectors. Two new stand- 

170 




Preparations of neutron time-of-flight experiment to measure neutron cross sec- 
tion of hydrogen (polyethylene sample at left-center). A compensating carbon 
sample is being adjusted. 




Absorbed-dose measurement apparatus showing the absorber wheel and graphite 
calorimeter block. Remote-control operation changes the absorber thickness 
and moves the calorimeter and comparison standards (not shown) parallel 
and perpendicular to a beam of electrons or x-rays. 



375-572—70 12 



171 



ards were developed: plutonium-238, which is the first NBS alpha- 
particle disintegration-rate standard; and thorium-228-thallium-208 
gamma-ray standard, for which a new method of calibration was devel- 
oped utilizing alpha-particle and gamma-ray counting methods. Work 
is almost complete on two new reference materials — nickel-63 solution 
standard and krypton-85 gamma-ray gas standard. 

High-Energy Electron and Photon Absorbed-Dose Standards — A 
calorimeter intended to be the basis for the Bureau's absorbed-dose 
calibration service was constructed and all tests preliminary to actual 
use were completed. The instrument will be used initially to determine 
the dose deposited in carbon by electron beams with energies from 30 to 
50MeV. 

Cobalt-60 Source Calibration — The exposure rate from a cobalt-60 
source furnished by the National Kesearch Council, Ottawa, Canada, 
was measured with the Bureau's standard cavity chamber. The meas- 
ured rate agrees within 1 percent with the rate predicted from the 
power output of the source as determined by calorimetry. 

High-Intensity Monoenergetic Photon Beams — Experimental 
studies are being carried out to develop high-intensity monoenergetic 
photon beams in the energy region from approximately 0.5 to 100 keV. 
These beams will be produced with electron accelerators by direct elec- 
tron excitation of K x rays in different targets. It is expected that for 
direct current accelerators, the beam intensities will be approximately 
three orders of magnitude larger than the current methods in which 
K x rays are produced by photon rather than by electron excitation. 

Nuclear Physics Research 

High-Energy Electron Scattering — A broad program of high- 
energy electron scattering is conducted using the NBS electron linac. 
The experimental apparatus is capable of measuring the spectrum of 
scattered electrons with a resolution of 0.08 percent. Inelastic scatter- 
ing from 12 C has been studied, concentrating on the excitation region 
17-27 MeV. The low lying excited states of 16 have been examined in 
an experiment made feasible by the unique high-resolution capability 
of the apparatus. In particular, it was possible to resolve the first two 
excited states near 6 MeV, separated by only 80 keV, and measure their 
form factors. This work is expected to contribute substantially to our 
understanding of the structure of this nucleus. Other experiments in 
progress are aimed at measuring the properties of the nuclei 13 C, 
19 F, 46 Ti, 48 Ti, 50 Ti, 88 Sr, and 89 Y. Many of these experiments are 
collaborative efforts with research teams from a number of universities. 

A study is in progress to measure the cross section for scattering 
of electrons from protons. The NBS apparatus is particularly well 
suited for this work in which the aim is to measure this very funda- 

172 



mental cross section with an accuracy substantially better than one 
percent. 

Nuclear-Structure Studies by Electron and Photon Excitation — 
The program to investigate the sy sterna tics of nuclear energy levels 
excited by electrons and photons is continuing. Experiments being 
actively carried on include excitation of nuclear levels in isotopes of 
hafnium, iridium, gold, and erbium with the possible inclusion of 
tungsten and mercury being considered. Systematic variations in the 
energy structures of these nuclei are being studied and the results 
being compared with existing theoretical calculations. 

Heavy-Ion Spectrometer Experiments — Successful and reliable 
operation of the heavy-ion spectrometer to measure charged particle 
spectra and angular distributions was achieved. Measurements were 
started on the cross section for the reaction, 4 He(y,cZ)D. An agree- 
ment was made with the University of Illinois to carry out a collabor- 
ative experiment to measure the cross sections for the photo disintegra- 
tion of the mass-3 nuclei ( 3 H and 3 He) . 

Nuclear Spectroscopy — The nuclear orientation of radioactive irid- 
ium-192 in a ferromagnetic matrix was studied in detail. The angular 
distribution of gamma rays and conversion electrons with respect to 
the nuclear spin direction was measured for eight electromagnetic 
transitions and the multipolarity mixtures for each of these transitions 
determined. A measurement of the beta ray angular and energy 
distributions determines the tensor rank of the matrix elements con- 
tributing to the beta transitions. A solid state beta detector and pre- 
amplifier operating at a temperature of 1.5 K and large germanium 
gamma ray detectors provided the necessary resolution and efficiency. 

Inelastic Electron Scattering — Following a previous large-angle, 
moderate-energy experiment, the data are being extended to include 
higher incident energies (up to 3 MeV), forward scattering angles 
(less than 90°), and low atomic number targets. These parametric 
studies are being carried out to determine the effects of the atomic 
binding of the target electrons on the observed scattered electron 
spectra. Disturbing variations from the available theoretical calcula- 
tions are still evident and the data are now in the process of being 
analyzed. 

Inelastic Electron Scattering Gross Sections — Investigations of 
inelastic electron scattering for 100-, 200-, and 400-keV electrons 
have shown low and high energy tails in the energy spectra of inelas- 
tically scattered electrons. In addition, the angular distribution of 
these electrons over the region from 20 to 180 degrees has shown a 
sharp maximum in the region of 90 degrees. 

Isospin Sum Rules for Photonuclear Reactions — The study of the 
electro-magnetic aspects of the three-nucleon system has continued. 
Three sum rules for the two isospin components in the 3 H and 3 He 

173 



photodisintegration reactions have been derived. One of these rules 
relates the photon absorption cross sections to the charge radii of the 
nuclei. This rule has also been generalized to other nuclei and provides 
a valuable guide to the prediction of the strengths of photoabsorption 
cross sections of the two final isospin states. 

The Photonuclear Data Center — Compilation and abstracting activ- 
ities have continued along with the preparations for publication of the 
second supplement to Miscellaneous Publication 277, the Photonuclear 
Data Index. This supplement, scheduled for publication early in FY 
70, will be an index to data published from January 1965 through 
the first half of 1969. Work was started on building up a computer- 
based library of photonuclear cross-section data. Over 150 cross-section 
curves have been digitized and entered in the data file. 

Radiation Theory 

High-Energy Physics — Assuming SU(6) W invariance of the meson- 
baryon amplitudes and a universality principle which connects these 
to the photoproduction amplitudes, it has been possible to describe the 
energy dependence of many forward photoproduction processes involv- 
ing pseudoscalar and vector mesons. For example, results obtained for 

the ratio ~ — jFTrT\ disagree with the simple quark model but fit 

much better with the experimental results. 

Encouraged by success in the photoproduction work, efforts were 
directed to the meson-baryon processes in an attempt to make some 
sense out of the apparent tremendous breakings of the symmetry 
there. It was found that the symmetry is broken in a rather regular, 
though still not understood, way which nevertheless allows quantita- 
tive predictions for forward and backward meson-baryon reaction 
cross sections. 

Meson Effects — A model calculation of the photoproduction of tt 
mesons from nucleons was completed, and numerical results which 
agree fairly well with existing experiments were obtained by fitting 
a single parameter. A calculation of the anomalous magnetic moment 
of the deuteron, allowing the admixture of nuclear resonances (N* 3 _ 3 
(1236), N*i_i(1470)) in the wave function, was made. Eesults were 
such as to improve agreement of existing calculations with experiment. 
Finite energy sum rules were used to predict high energy behavior of 
meson-baryon scattering amplitudes, using low energy experimental 
data for these processes as input. New mathematical properties of the 
finite energy sum rules were explored and exploited. 

Electron Transport Theory — In continuing study of electron trans- 
port using Monte Carlo techniques, calculations have been made of 
electron transmission and reflection, energy deposition, and brem- 

174 



sstrahlung production in thick targets. Specific applications have in- 
cluded determination of the spatial distribution of energy deposition 
in the atmosphere by auroral electrons (2 to 20 keV), in the presence 
of the earth's magnetic field ; calculation of the response of Si detectors 
to electrons with energies from 0.15 to 5.0 MeV; and calculation of the 
electron flux generated in water by electrons and bremsstrahlung 
beams with energies up to 60 MeV. 

A code has been developed which will calculate the energy deposi- 
tion by electrons in multilayer media. These calculations have 
applications in determining the dynamic response of solids by laser 
interferometric techniques. The production of characteristic K x rays 
and bremsstrahlung has also been calculated. 

Quantum Electrodynamics — Higher order radiative corrections to 
the scattering of electrons from nuclei at high momentum transfers 
were studied with the aim of permitting more accurate analysis of data 
from the newer linear accelerators. In particular, radiative corrections 
to the scattering cross section in second Born approximations, and the 
radiative tails in the same approximation, are being calculated. 

Time Reversal — The first direct demonstration that time reversal 
symmetry (T) is violated in K° meson decay has been given. Hereto- 
fore T violation has only been inferred indirectly via the known OP 
violation and the OPT theorem. However, OPT symmetry itself is be- 
ing tested in K° decays. (The T test is more sensitive.) This work was 
published in a journal series and has received attention in the technical 
news magazines. It is relevant to the current search for an electric 
dipole moment of the neutron, in which the NBS high-flux reactor may 
play a role. 

The mathematical techniques involved in K° decays have also been 
applied to a study of energy transfer between impurities in matter. 
Mechanisms of energy transfer are currently of biologic interest. Addi- 
tional papers on charge transport in stressed matter and on photo- 
production of phonons have been prepared. 

Structure of Materials 

Dynamics and Interionic Forces in Phosphonium Salts — The vibra- 
tional and rotational dynamics of phosphonium halide crystals have 
been studied by Laser-Raman and NMR spectroscopy in cooperation 
with other groups at NBS and the University of Maryland. A com- 
parison of the spectroscopic results with previous structural informa- 
tion suggests that the crystal potential hindering the rotation of the 
phosphonium ions is dominated by short-range repulsive forces. The 
results are in sharp contrast to those for the isostructural ammonium 
salts. It is hoped that continued neutron diffraction and inelastic 
scattering studies on these crystals, combined with theoretical cal- 

175 



culations, will yield generally consistent force models for both 
ammonium and phosphonium salts. 

Phase Transitions in Metal Hydrides — The lattice vibrations and 
diffusion of hydrogen in several phases of vanadium hydride have 
been studied by quasielastic and inelastic neutron scattering in collab- 
oration with scientists at Argonne National Laboratory. The 
a < — > /3 phase transition has been shown to be associated with a very 
large change in the hydrogen diffusion rate. In addition, an abnor- 
mally low activation energy for diffusion and a large concentration 
dependence for the diffusion is found in the a phase. These observa- 
tions, coupled with significant differences in the vibration spectra 
for the «, /?, and y phases, suggest that the transitions are associated 
with a reordering of the hydrogens. The implications of these results 
with respect to the properties of other transition -metal hydrides are 
being studied. 

Facilities Operations 

Linear Accelerator — During fiscal year 1969 approximately 1700 
hours of beam time were provided for experiments using the NBS 
linac. This was 63.4 percent of the scheduled beam time. Continued 
modifications to the accelerator and beam transport equipment have 
been accomplished to improve beam quality and reduce maintenance. 
The fraction of the scheduled time during which beam was delivered 
to experiments has increased 11 percent over the corresponding figure 
for FY 68. This increase was largely due to the fact that for about 
20 percent of the year it was possible to operate the linac round-the- 
clock on a four day a week schedule. The beneficial impact of this 
round-the-clock operation was somewhat impaired by a series of 
injector problems, but was still very significant both to the accelerator 
performance and to experiments. 

Experiments using the accelerator include programs in electron 
scattering, photoneutron production, production of heavy ions, meas- 
urement of neutron total absorption cross sections, studies in beam 
monitoring, tests of accelerator theory, programs in activation 
analysis, and production of radioactive sources for materials studies 
using Mossbauer sources and for studies of photonuclear reactions. 
Programs in electron and x-ray beam dosimetry, accelerator research, 
production and use of monoenergetic positron and photon beams, 
studies of transient chemical reactions, and studies of neutron capture 
gamma rays are in preparation. 

Use of the linac by organizations outside of CRR has increased 
appreciably during this period. For groups outside of NBS most of 
this use is in collaborative programs with KBS personnel. There are 
presently 25 Guest Workers representing 12 organizations outside 
NBS (mostly universities) involved in programs using the linac. Most 

176 



of these Guest Workers spend a relatively small fraction of their 
time at NBS, doing the analysis of their data at their home institu- 
tions. Experimental data-taking for two doctoral theses was com- 
pleted this year, with preliminary data-taking started for five other 
doctoral candidates. Work using the NBS linac that was supported by 
six other government agencies was carried out during this period. 

Accelerator Research — A problem of long-standing interest in the 
theory of linear electron accelerators is the ultimate beam current 
possible for extremely short, high-intensity beams. This question is 
directly related to the energy lost by such a beam due to microwave 
excitation of the accelerating structure. The loading by very short 
beam bursts might be expected to be large due to the broad frequency 
spectrum implied by short beam bursts ; however, theoretical estimates 
of these effects differ considerably in the magnitude of the effect, and 
even in the dependence on electron energy. The existence of enhanced 
beam loading for short pulses is of particular importance for a new 
electron ring accelerator concept presently being studied in the USSR 
and at the University of California. An experiment has been per- 
formed to measure these effects using low beam currents under pre- 
cisely controlled experimental conditions. The energy lost by a very 
short (few nanosecond) electron beam pulse in passing through an 
accelerating waveguide was measured. Energy shifts of a few parts 
in 10 5 were detectable. Enhanced beam loading, consistent with some 
theoretical predictions, was observed. 

4,-MeV Accelerator — Improvement and updating of the NBS 4-MeV 
Van de Graaff electron accelerator is continuing, with most modifica- 
tions occurring in the peripheral experimental equipment to increase 
its flexibility and usefulness for the largest possible number of diverse 
experiments. Such improvements are typified by the addition of a new 
180° scattering chamber designed to study electron-produced gamma 
and x rays at large scattering angles. The existing 18-in scattering 
chamber has also been outfitted with a new target-holding mechanism 
which allows the experimenter to mount a variety of different targets 
and to change the inclination of the target to the incident beam direc- 
tion without cycling the vacuum system. In addition to the experi- 
mental programs of the Bureau, a number of outside users have and are 
utilizing this facility for numerous experimental projects. 

180 MeV Synchrotron — The move of the NBS Synchrotron from 
the old NBS site to Gaithersburg was completed early in the fiscal year. 
Electron beam current is generally about twice what it was in Wash- 
ington with better stability. The accelerator is used almost exclusively 
as a far ultraviolet light source by the Atomic Physics Division, IBS. 
With new experimental apparatus the light may be used at several 
points simultaneously, thus greatly increasing utilization of the 
accelerator. 

177 



liiigp 



■■■■■■■■■■■ ■ 



i ~ So 







IlltP 






illllfiilllllPllJ^ f: 




Far ultraviolet light is transmitted through tangential port (left-foreground) of 
donut resting on magnet of NBS Synchrotron — seen herefrom above. 



Isotope Separator — A large number of irradiations have been car- 
ried out with the isotope separator in the last year. Oxygen and neon 
isotopes were implanted into niobium foil for Pennsylvania State 
University for nuclear-excitation experiments ; iron- 57 was implanted 
into aluminum in connection with the development of a Mossbauer 
detector for the NBS Analytical Chemistry Division and the Atomic 
Energy Commission ; aluminum-27 and chromium- 52 were implanted 
into silicon crystals, and krypton-86, on a special target, for the Naval 
Research Laboratory ; bismuth-209 was irradiated in the NBS linear 
electron accelerator and separated and examined in the low-level 
counting facility, with some indication of radioactivity down to mass 
200. A technical note on praeseodymium profiles and penetration in 
iron foils, in connection with nuclear orientation experiments, was pre- 
sented at the International Isotope Separator Conference held in 
Brookhaven in September 1969. 

Technical Assistance to Others 

Shielding for Civil Defense — Changes in the methods used by the 
Office of Civil Defense to calculate shielding properties of structures 
against fallout, which were recommended by NBS, have been adopted 
by OCD. Recommendations on procedures for calculating protection 
from nuclear weapons are being generated by NBS. 

178 



Particle Accelerator Conference — The third Particle Accelerator 
Conference was held at the Shoreham Hotel, Washington, D.C. on 
March 5-7, 1969. Approximately 800 persons from industry, national 
laboratories, universities, and Government agencies attended. Al- 
though it was organized as a national conference, the proceedings were 
enriched by significant foreign participation. The purpose of the Con- 
ference was to promote and to facilitate communication among sci- 
entists and technologists engaged in the planning, design, and opera- 
tion of all types of particle accelerators and related devices. 



179 



APPENDIXES 



ORGANIZATION OF THE NATIONAL 
BUREAU OF STANDARDS 1 



The Bureau is headed by a Director who is appointed by the Presi- 
dent with the advice and consent of the Senate. The Director is assisted 
in the overall management of the Bureau by a Deputy Director. An 
Associate Director for Administration is responsible for the planning 
and operation of facilities and of administrative management serv- 
ices in support of the Bureau's technical programs. An Associate Di- 
rector for Information Programs is responsible for the dissemination 
and accessibility of scientific and technological information. 

Technical program activities are conducted in three Institutes and 
two Centers. Each is headed by a Director who is responsible for the 
development and direction of research programs and central national 
services essential to the fulfillment of a broad segment of the Bureau's 
mission. These major organizational units are: 

(1) The Institute for Basic Standards, which includes the Office of 
Measurement Services and 11 technical divisions (5 in Boulder, Colo- 
rado) each serving a classical subject matter area of science and en- 
gineering; also in IBS are 3 administrative divisions serving the 
technical divisions located at Boulder ; 

(2) The Institute for Materials Research, which consists of 6 di- 
visions, organized primarily by technical field ; 

(3) The Institute for Applied Technology, which includes 10 divi- 
sions oriented to high technology industries ; 

(4) The Center for Radiation Research, which includes 4 divisions 
concerned with the theory and application of radiation ; and 

(5) The Center for Computer Sciences and Technology, which 
includes 5 divisions concerned with the selection, acquisition, and 
utilization of automatic data processing equipment. 



1 As of June 30, 1969. 

181 



DIRECTOR 

Allen V. Astin* 

DEPUTY DIRECTOR 

L. M. KlJSHNER 

OFFICE OF THE DIRECTOR 

Assistants to the Director 
G. E. Auman 

C. N". COATES 

R. D. Htjntoon 
A. G. McNish 

Special Assistant for Program Planning 
R. E. Ferguson 

Legal Advisor 
A. J. Farrar 

Office of Academic Liaison 
S. Silverman 

Senior Research Fellow 
C. Eisenhart 

Staff Units Reporting to the Deputy Director 

Office of Industrial Services G. S. Gordon 

Office of Engineering Standards Liaison A. A. Bates 

OFFICE OF ASSOCIATE DRECTOR FOR ADMINISTATION 

R. S. Walleigh 
Deputy Associate Director 

P. H. SCHRADER 

Patent Advisor 

D. ROBBINS 

Accounting Division J. P. Menzer 

Administrative Services Division G. W. Knox 

Budget Division J. E. Skillington 

*Dr. Astin retired on August 31, 1969. 

182 



Management and Organization Division J. T. Hall 

Personnel Division G. R. Porter 

Plant Division H. Graham 

Supply Division N. H. Taylor 

OFFICE OF THE ASSOCIATE DIRECTOR FOR 
INFORMATION PROGRAMS 

E. L. Brady 

Assistant for Program Coordination and Evaluation 
P. H. Kratz, Acting 

Office of Standard Reference Data D. R. Lide, Jr. 

Atomic and Molecular Data Data Systems Design 

Chemical Kinetics Mechanical Properties 

Colloid and Surface Chemistry Nuclear Data 

Information Services Solid State Properties 

Thermodynamics and Transport Data 

Clearinghouse for Federal Scientific and Technical 

Information H. E. Sauter 

Document Distribution Joint Publications Research 

and Reproduction Document Processing 

Automated Systems and 
Services 

Administrative Operations 

Office of Technical Information and Publications W. R. Tilley 

Special Activities Photographic Services 

Editorial Graphic Arts 

Publications Computer Assisted Printing 

Library Division E. L. Tate 

Resources Development Reader Services 

Library Auxiliaries 

Office of Public Information A. V. Gentilini 

Office of International Relations H. S. Peiser, Acting 



183 



INSTITUTE FOR BASIC STANDARDS 

Director 
E. Ambler 

Assistant Director 
R. J. Corruccini 

Deputy Director, Institute for Basic Standards/Boulder x 
B. W. Birmingham 

Office of Measurement Services 
J. M. Cameron 

Applied Mathematics E. W. Cannon 

Numerical Analysis Statistical Engineering 

Operations Research Systems Dynamics 

Electricity Division C. H. Page 

Resistance and Reactance High Voltage 

Electrochemistry Absolute Electrical 

Electrical Instruments Measurements 

Metrology Division . K. G. Kessler, Acting 

Photometry Length 

Image Optics and Photography Engineering Metrology 

Colorimetry and Spectrophotometry Mass and Volume 

Mechanics Division L. K. Irwin 

Sound Hydraulics 

Vibration Measurements Aerodynamics 

Engineering Mechanics Pressure Measurements 

Rheology Vacuum Measurements 

Fluid Meters Humidity Measurements 

Heat Division R. P. Hudson 

Heat Measurements Statistical Physics 

Cryogenic Physics Temperature 

Equation of State Radiation Thermometry 

Atomic and Molecular Physics Division K. G. Kessler 

Spectroscopy Molecular Spectroscopy 

Infrared Spectroscopy Electron Physics 

Far Ultraviolet Physics Atomic Physics 

Plasma Spectroscopy 

Radio Standards Physics Division 1 H. S. Boyne 

Solid State Electronics Quantum Electronics 

Plasma Physics 

Radio Standards Engineering Division 1 R. C. Sangster 

HF Impedance Standards Microwave Calibration Service 

RF Transmission and Noise Microwave Circuit Standards 

RF Power and Voltage Electromagnetic Field Standards 

Time and Frequency Division 1 J. A. Barnes 

Frequency-Time Dissemination Frequency-Time Broadcast Services 

Research 

1 Located at Boulder, Colorado. 



184 



Atomic Frequency-Time Standards 

Laboratory Astrophysics Division 1 L. M. Branscomb* 

Cryogenics Division 1 D. B. Chelton, Acting 

Cryogenic Technical Services Properties of Cryogenic Fluids 

Cryogenic Data Center Cryogenic Systems 

Cryogenic Properties of Solids Cryogenic Metrology 

Cryogenic Fluid Transport Processes 

Administrative Services Division 1 B. F. Betts 

Supply Office Services 

Drafting Services 

Instrument Shops Division 1 W. A. Wilson 

Instrument Shops 1 & 2 Welding-Sheet Metal 

Glassblowing Shop 

Plant Division 1 E. A. Yuzwiak 

Construction-Maintenance Special Services 

Custodial Services 

INSTITUTE FOR MATERIALS RESEARCH 

Director 
J. D. Hoffman 

Assistant Director 
E. Hokowitz 

Office of Standard Reference Materials J. P. Cali, Acting 

Analytical Chemistry Division W. W. Meinke 

Radiochemical Analysis Microchemical Analysis 

Spectrochemical Analysis Analytical Mass Spectrometry 

Electrochemical Analysis Organic Chemistry 

Analytical Coordination Activation Analysis 

Chemistry 

Separation and Purification 

Polymers Division R. K. Eby, Acting 

Polymer Dielectrics Dental Research 

Polymer Chemistry Polymer Characterization 

Polymer Crystal Physics Polymer Interfaces 

Molecular Properties Thermophysical Properties 

Metallurgy Division E. Passaglia 

Engineering Metallurgy Corrosion 

Alloy Physios Metal Physics 

Lattice Defects and Micro- Electrolysis and Metal Deposition 

structures 

Crystallization of Metals 

Inorganic Materials Division J. B. Wachtman, Jr. 

Inorganic Chemistry Physical Properties 

Inorganic Glass Crystallography 

High Temperature Chemistry Solid State Physics 

Physical Chemistry Division J. R. McNesby, Acting 

Thermochemistry Mass Spectrometry 

Surface Chemistry Photo Chemistry 

Elementary Processes Radiation Chemistry 

*Dr. Branscomb became director of the National Bureau of Standards on September 1, 
1969. 

1 Located at Boulder, Colorado. 



185 



INSTITUTE FOR APPLIED TECHNOLOGY 

Director 
H. E. Sorrows, Acting 

Deputy Director 

M. W. Jensen, Acting 

Office of Engineering Standards Services D. R. Mackay 

Product Standards Section Information Section 

Mandatory Standards Section 

Office of Weights and Measures T. M. Stabler, Acting 

Office of Invention and Innovation D. V. DeSimone 

Innovation Studies Program Invention Programs 

Engineering Education Program 

Office of Vehicle Systems Research P. J. Brown 

Tire Systems Occupant Restraint Systems 

Braking Systems 

Product Evaluation Division S. B. Newman* 

Plastics and Textiles Paper Evaluation 

Fibrous Systems Fabric Flammability 

Viscoelastic Materials 

Building Research Division J. R. Wright 

Structures Materials Durability and Analysis 

Fire Research Codes and Standards 

Scientific and Professional Liaison Building Systems 

Sensory Environment Branch 
Environmental Engineering Psycho-physics 

Building Transport Systems 

Electronic Technology Division M. G. Domsitz 

Semiconductor Characterization Instrumentation Applications 

Electron Devices Semiconductor Processing 

Technical Analysis Division W. E. Cushen 

Transportation and Highway Studies Economic Analysis 
Systems Analysis and Human Development of New Methodology 

Factors 

Instrument Shops Division F. P. Brown 

Instrument Shops 1-5 Optical Shop 

Glassblowing Tool Crib 

Welding and Sheet Metal Electroplating Shop 

Measurement Engineering Division G. F. Montgomery 

Electronic Instrumentation Electronic Optical Development 

Microwave and Mechanical Instrumentation 

CENTER FOR RADIATION RESEARCH 

Director 

C. O. MUEHLHATJSE 

Deputy Director 
R. S. Caswell 

Radiation Theory Health Physics 



*Now M. R. Meyerson. 

186 



Reactor Radiation Division R. S. Carter 

Reactor Operations Neutron Solid-State Physics 

Engineering Services Radiation Effects 

Linac Radiation Division J. E. Leiss 

Linac Operations Photonuclear Physics 

Radiation Physics Instrumentation Electronuclear Physics 

Nuclear Radiation Division H. H. Landon 

Nuclear Physics Radioactivity 

Nuclear Spectroscopy Section 

Applied Radiation Division J. W. Motz 

X-Ray Physics Dosimetry 



CENTER FOR COMPUTER SCIENCES AND TECHNOLOGY 

Director 

H. R. J. Grosch 

Office of Information Processing Standards J. O. Harrison, Jr. 

Planning and Coordination Software Standards 

Hardware Standards Applications and Data Standards 

ADP Management Standards 

Office of Computer Information M. R. Fox 

Computer Services Division W. B. Ramsay 

Business Applications Computer Operations 

Scientific Applications Systems Programming and Training 

Systems Development Division C. T. Meadow 

Programming Research Management Systems 

Information Science Instructional Systems 

Information Processing Technology Division J. P. Nigro 

Measurement Automation Computer Systems 

Performance Measurements 



FIELD ESTABLISHMENTS 

Institute for Basic Standards 

Metrology Division Field Station: 

Visual Landing Aids Field Laboratory Areata, California 

Time and Frequency Division Field Station: 

Standard Frequency Station WWV-WWVL-WWB Fort Collins, Colorado 

Standard Frequency Station WWVH Maui, Hawaii 

Laboratory Astrophysics Division Field Station : 

Poor Man's Relief Mine, Four-Mile Canyon Boulder, Colorado 

Institute for Applied Technology 

Office of Weights and Measures Field Stations: 

Master Railway Track Depot Clearing, Illinois 



375-572—70 13 



187 



2, 867 


566 


3,433 


502 


68 


570 


3, 369 


634 


4,003 


135 


15 


150 


3, 504 


649 


4, 153 


401 


114 


515 


263 


6 


269 


181 


82 


263 


47 


4 


51 


130 


7 


137 



SUMMARY OF NBS STAFF AS OF JUNE 30, 1969 

Washington Boulder Total 

Full-time permanent staff l 

Other staff 2 

Total paid staff 

Research associates and guest workers. _ 

Total NBS staff 

Professional staff with academic degrees: 

Physicists 

Chemists 

Engineers 

Mathematicians 

Other 

Total 1,022 213 1,235 

1 Includes Post Doctoral Research Fellows. 

2 Summer, Youth Opportunity Corps, Part-time, Intermittent and Temporary. 

FINANCIAL DATA FOR FISCAL YEAR 1969 

Obligations 
Program and source of financing incurred in 

Supported by NB S Appropriations ^dollar! 

Operating programs : (rounded) 

Research and technical services $36, 100 

Civilian industrial technology . 39 

Special foreign currency program 900 

Construction and facilities programs : 

Plant and facilities 2, 441 

Construction and facilities 2, 793 

Total obligations, NBS appropriations 42,273 

Supported by other funds : x 

From other Federal agencies 24, 960 

From other sources 4, 073 

Total obligations, other funds 29, 033 

Total program 71, 306 

1 Work supported by other funds consists of research and development programs for other 
Government agencies ; consultative, advisory, and technical services, the performance of 
various tests and calibrations, and the manufacture and sale of standard reference mterials 
for other Government agencies and the public. 

RESEARCH ASSOCIATES AND GUEST WORKERS 

Research Associates and Their Sponsors 
During Fiscal Year 1969 

American Dental Association 
Argentar, Mr. Harold 
Bowen, Mrs. Joy C. 
Bowen, Dr. Rafael L. 
Brown, Dr. Walter E. 
Brunetti, Dr. Anthony P. 

188 



Carlson, Mr. Elmer T. 
Caul, Mr. Harold J. 
Chandler, Mr. Harry H. 
Gregory, Mr. Thomas M., Jr. 
Kinshury, Mrs. Pamela 
Mabie, Mr. Curtis P., Jr. 
Manuszewski, Mr. Richard 0. 
McDowell, Mr. Hershel 
Moreno, Dr. Edgard C. 
Paffenbarger, Dr. George C. 
Palcic, Miss Julia M. 
Patel, Mr. Praful 
Rupp, Dr. Nelson Woodward 
Wallace, Mrs. Betty M. 
Waterstrat, Mr. Richard M. 

America^ Electroplaters Society 
Johnson, Mr. Christian E. 

American Society for Testing and Materials 
Bell, Mrs. Jacqueline Y. 
de Groot, Mr. Johan H. 
Evans, Mrs. Eloise H. 
Grimes, Mr. John W., Jr. 
McMurdie, Mr. Howard F. 
Morris, Mrs. Marlene C. 

American Society for Testing and Materials (Concrete and Concrete Reference 
Laboratory ) 

Anderson, Mr. Harry G., Jr. 

Atkinson, Mr. George O., Jr. 

Dise, Mr. John R. 

Johnson, Mr. Marlin C. 

Katz, Mrs. Anne K. 

Liskey, Mr. John F. 

McCarthy, Mr. Dennis D. 

Spring, Mr. Curtis B. 

Sturm, Mr. William F. 

Wallace, Mr. Dennis R. 

American Viscose Division (FMC Corporation) 
Oneal, Mr. Glen, Jr. 

3 ell Aero systems 
Rogers, Ernest E. 

Children's Hospital 
Bora sky, Dr. Rubin 

Consumers Union of U.S., Inc. 
Kanagy, Dr. Joseph R. 

Control Data Corporation 
Buckland, Mr. Stanley, F., Jr. 

lorn Refiners Association, Inc. 
Thomas, Mr. James H. 
Vomhof , Dr. Daniel W. 

lorning Glass Worfos 
Justice, Mr. Benjamin 

)ow Chemical Company 
Hamilton, Mr. Robert M. 

lastman Kodak Company 
Prsybylowicz, Dr. Edwin P. 



189 



Electrical Testing Laboratories, Inc. 
Mohan, Mr. Kshitij 

Factory Mutual Research Corporation 
Kappraff, Mr. Ronald M. 
Orloff, Mr. Lawrence 
Roekett, Dr. John A. 
Torrance, Dr. Kenneth E. 

International Business Machines Corporation 
Cleveland, Mr. Norman G. 
Phillips, Dr. Sidney L. 

Japan Electronic Industry Development Association 
Yamadori, Mr. Yuji 

Kennecott Copper Corporation 
Harvey, W. William 

Manufacturing Chemists Association 
Clark, Mr. Joseph E. 
Gill, Paul C. 

Herndon, Mr. John L., Ill 
Slater, James Alan 

Martin Marietta Corporation (Research Institute for Advanced Studios) 
Mengenberg, Dr. Hans-Dieter 

Nippon Electric Company (Japan) 
Inawashiro, Mr. Tutomu 

Owens-Corning Fiberglas Corporation 
Fitch, Mr. William E. 

Porcelain Enamel Institute 
Burdick, Mr. Milton D. 
Baker, Mrs. Margaret A. 
Gugeler, Mr. Lauren A. 

State of Maryland, 
Benjamin, Arthur 

Underwriters Laboratories, Inc. 
Castino, Mr. Guy T. 

U.S. Navy Marine Engineering Laboratory 
Arora, Dr. Om P. 

U.S. Naval Ship Research & Development Center 
Hammond, Barry L. 

U.S. Steel Corporation 
Martin, Mr. John F. 
Swartz, John C. 

ADVISORY COMMITTEES 
STATUTORY VISITING COMMITTEE 

The Statutory Visiting Committee was established by Act of Congress to ad- 
vise the Secretary of Commerce and the Director of NBS. This committee is ap- 
pointed by the Secretary of Commerce. It meets at the call of its chairman. Dates 
indicate expiration of appointment. 

Dr. Robert L. Sproull, Vice President, University of Rochester (1971), 

Chairman 
Prof. Norman F. Ramsey, Dept. of Physics, Harvard University (1970) 

190 



Dr. E. R. Piore, Vice President & Chief Scientist, International, Business 

Machines Corporation (1972) 
Dr. Elmer W. Engstrom, President, Radio Corporation of America (1973) 
Dr. J. E. Goldman, Senior Vice President, Research & Development, Xerox 

Corporation (1974) 

TECHNICAL ADVISORY PANELS 

The panels advisory to the National Bureau of Standards were established in 
1959 under the terms of a contract between the National Bureau of Standards 
and the National Academy of Sciences. The Advisory Panels are responsible to 
the National Academy of Sciences-National Academy of Engineering-National 
Research Council, Division of Physical Sciences. One panel is established for 
each of the three Institutes of the Bureau, and one panel for each of the major 
divisions within the Institutes. The advisory panels to the Institute for Applied 
Technology are appointed by the President of the National Academy of Engi- 
neering. Ail other panels are appointed by the President of the National Academy 
of Sciences. The divisional panels ordinarily have eight members although by 
special arrangement a few have more or less. Terms are usually three years. 

Institute for Basic Standards 

Advisory Panel to Institute for Basic Standards 

Dr. William G. Amey, Leeds & Northrup Company 

Dr. John A. Hornbeck, Sandia Corporation 

Prof. John Todd, California Institute of Technology 

Mr. Eric J. Schneider, Engis Equipment Company 

Prof. S. R. Beitler, American Society of Mechanical Engineering 

Dr. E. F. Hammel, University of California 

Dr. Wade L. Fite, University of Pittsburgh 

Prof. Sanborn C. Brown, Massachusetts Institute of Technology 

Dr. Paul D. Coleman, University of Illinois 

Mr. Nathan Cohn, Leeds and Northrup Company 

Prof. Robert Novick, Columbia University 

Dr. Clyde McKinley, Air Products and Chemicals, Inc. 

Advisory Panel to Applied Mathematics Division 

Prof. John Todd, Chairman California Institute of Technology 

Prof. Francis J. Anscombe, Yale University 

Prof. Philip J. Davis, Brown University 

Prof. Charles R. DePrima, California Institute of Technology 

Prof. H. O. Hartley, Texas A. & M. University 

Prof. M. H. Martin, University of Maryland 

Prof. Marvin L. Minsky, Massachusetts Institute of Technology 

Prof. John Riordan, The Rockefeller University 

Advisory Panel to Electricity Division 

Dr. William G. Amey, Leeds & Northrup Company, Chairman 

Prof. Raymond M. Fuoss, Yale University 

Prof. H. N. Hayward, University of Illinois 

Mr. William J. Johnson, Philadelphia Electric Company 

Prof. George B. Hoadley, North Carolina State University 

Dean R. B. Lindsay, Brown University 

Mr. S. C. Richardson, General Electric Company 

Mr. Douglas C. Strain, Electro Scientific Industries, Inc. 

Advisory Panel to Metrology Division 

Mr. Eric J. Schneider, Engis Equipment Company, Chairman 

Prof. Isay A. Balinkin, University of Cincinnati 

Mr. B. R. Buus, General Electric Company 

Dr. Alsoph H. Corwin, The Johns Hopkins University 

Mr. J. K. Emery, The Van Keuren Company 

Dr. Robert E. Hopkins, University of Rochester 



191 



Mr. Louis Polk, Dayton, Ohio 

Dr. George J. Zissis, University of Michigan 

Advisory Panel to Mechanics Division 

Prof. S. R. Beltler, American Society of Mechanical Engineering, Chairman 

Prof. Lynn S. Beedle, Lehigh University 

Dr. B. B. Dayton, The Bendix Corporation 

Prof. Cyril M. Harris, Columbia University 

Dr. Arthur T. Ippen, Massachusetts Institute of Technology 

Dr. Harry F. Olson, RCA Laboratories 

Prof. R. S. Rivlin, Lehigh University 

Dr. M. E. Shank, Pratt & Whitney Aircraft 

Advisory Panel to Heat Division 

Dr. E. F. Hammel, University of California, Chairman 

Prof. G. B. Beneclek, Massachusetts Institute of Technology 

Prof. John E. Kilpatrick, Rice University 

Dr. James E. Mercereau, California Institute of Technology 

Dr. John P. McCullough, Mobil Oil Corporation 

Dr. James W. Moyer, Northrop Corporation. 

Prof. John G. Phillips, University of California 

Prof. Howard Reiss, University of California 

Advisory Panel to Atomic and Molecular Physics Division 

Dr. Wade L. Fite, University of Pittsburgh, Chairman 

Prof. C. O. Alley, University of Maryland 

Dr. James E. Drummond, Boeing Scientific Laboratories 

Prof. Vernon W. Hughes, Yale University 

Prof. Richard C. Lord, Massachusetts Institute of Technology 

Prof. Robert Novick, Columbia University 

Prof. W. E. Spicer, Stanford University 

Prof. George Wallerstein, University of Washington 

Advisory Panel to Radio Standards Physics Division 

Prof. Sanborn C. Brown, Massachusetts Institute of Technology, Chairman 

Dr. George Birnbaum, North American Aviation Science Center 

Dr. Arnold L. Bloom, Spectra-Physics 

Prof. A. Javan, Massachusetts Institute of Technology 

Dr. Josua Menkes. Institute for Defense Analyses 

Dr. Robert W. Terhune, Ford Motor Company 

Advisory Panel to Radio Standards Engineering Division 
Dr. Paul D. Coleman, University of Illinois, Chairman 
Mr. Stuart L. Bailey, Atlantic Research Corporation 
Mr. Ray Bailey, Newark Air Force Station 
Prof. Herbert J. Carlin, Cornell University 
Dr. Archie Gold, Army Ballistic Defense Agency 
Mr. Theodore S. Saad, Sage Laboratories, Inc. 
Mr. C. E. White, AVCO Corporation 

Advisory Panel to Time and Frequency Division 

Mr. Nathan Cohn, Leeds and Northrup Company, Chairman 

Dr. L. S. Cutler, Hewlett-Packard Company 

Dr. John M. Holt, Research Mathematics Group 

Mr. Chesley Looney, National Aeronautics and Space Admin. 

Dr. A. O. McCoubrey, Varian Associates 

Dr. J. A. Pierce, Harvard University 

Dr. Gemot M. R. Winkler, U.S. Naval Observatory 

Advisory Panel to Laboratory Astrophysics Division 

Prof. Robert Novick, Columbia University, Chairman 

Dr. James E. Drummond, Boeing Scientific Research Laboratories 

Dr. John W. Evans, Air Force Cambridge Research Laboratory 

Prof. Ronald Geballe, University of Washington 

Dr. Wayland C. Griffith, Lockheed Missiles & Space Company 

Dr. George H. Herbig, University of California 

192 



Prof. Dudley Herschbach, Harvard University 
Dr. John A. Hornbeck, Sandia Corporation 
Prof. Robert P. Kraft, University of California 

Advisory Panel to Cryogenics Division 

Dr. Clyde McKinley, Chairman Allentown Laboratories 

Dr. Frederick J. Edeskuty, Los Alamos Scientific Laboratory 

Dr. Alan M. Lovelace, Air Force Materials Laboratory 

Dr. William R. Lucas, National Aeronautics and Space Administrate 

Dr. John L. Mason, AiResearch Manufacturing Company 

Dr. J. V. Sengers, University of Maryland 

Advisory Panel to Institute for Materials Research 
Dr. William P. Slichter, Bell Telephone Laboratories 
Dr. William O. Baker, Bell Telephone Laboratories 
Prof. John Bardeen, University of Illinois 
Dr. Arthur Bueche, General Electric Research Laboratory 
Prof. L. B. Rogers, Purdue University 
Prof. Walter H. Stockmayer, Dartmouth College 
Dr. J. H. Crawford, University of North Carolina 
Prof. John E. Willard, University of Wisconsin 

Advisory Panel to Analytical Chemistry Division 

Prof. L. B. Rogers, Purdue University, Chairman 
Prof. Walter J. Blaedel, University of Wisconsin 
Dr. T. S. Burkhalter, Texas Instrument Company 
Mr. M. D. Cooper, General Motors Corporation 
Dr. John F. Flagg, American Cyanamid Company 
Dr. Vincent P. Guinn, Gulf General Atomic, Inc. 
Dr. N. B. Hannay, Bell Telephone Laboratories 
Prof. Sidney Siggia, University of Massachusetts 
Dr. Ralph E. Thiers, Bio Science Laboratories 

Advisory Panel to Polymers Division 

Prof. Walter H. Stockmayer, Dartmouth College, Chairman 

Dr. Raymond F. Boyer, Dow Chemical Company 

Dr. Frederick J. Fowkes, Lehigh University 

Dr. Fred Leonard, Walter Reed Army Medical Center 

Prof. Carl S. Marvel, University of Arizona 

Dr. Fraser P. Price, University of Massachusetts 

Prof. Duane F. Taylor, University of North Carolina 

Prof. Bruno H. Zimm, University of California 

Advisory Panel to Metallurgy Division 

Dr. Walter A. Dean, Aluminum Company of America 

Dr. G. J. Dienes, Brookhaven National Laboratory 

Dr. Julius J. Harwood, Ford Motor Company 

Dr. Richard A. Oriani, United States Steel Corporation 

Dr. Robb M. Thomson, State University of New York 

Prof. David Turnbull, Harvard University 

Dr. H. G. F. Wilsdorf , University of Virginia 

Advisory Panel to Inorganic Materials Division 

Dr. J. H. Crawford, University of North Carolina, Chairman 

Dr. George J. Bair, Corning Glass Works 

Dr. Theodore L. Brown, University of Illinois 

Dr. Harris M. Burte, Air Force Materials Laboratory 

Prof. Clyde A. Hutchison, Jr., The University of Chicago 

Dr. J. S. Kasper, The General Electric Company 

Prof. John L. Margrave, Rice University 

Prof. Alan M. Portis, University of California 

Dr. Elias Snitzer, American Optical Company 

Prof. J. H. Van Vleck, Harvard University 

Advisory Panel to Physical Chemistry Division 

Prof. John E. Willard, University of Wisconsin, Chairman 



193 



Professor Kyle D. Bayes, University of California 

Dr. Hartwell F. Calcote, AeroChem Research Laboratories, Inc. 

Dr. F. G. Ciapetta, W. R. Grace & Company 

Dr. R. E. Fox, Westinghouse Electric Corporation 

Prof. B. S. Rabinovitch, University of Washington 

Prof. T. N. Rhodin, Cornell University 

Dr. Bruno J. Zwolinski, Texas A. & M. University 

Advisory Panel to Institute for Applied Technology 

Mr. Kenneth C. Allen, Hobart Manufacturing Company 

Dr. Robert A. Hechtman, McLean, Virginia 

Dr. Leon Podolsky, Pittsfield, Massachusetts 

Prof. Philip Morse, Massachusetts Institute of Technology 

Dr. Jack Moshman, LEASCO Systems & Research Corporation 

Dr. W. J. Harris, Jr., Battelle Memorial Institute 

Dr. Carl H. Madden, U.S. Chamber of Commerce 

Dean Joseph R. Passonneau, Skidmore, Owens & Merrith 

Mr. Jacob Rabinow, Bethesda, Maryland 

Mr. Paul Strassmann, National Dairy Products Corporation 

Mr. Michael Witunski, McDonnell Douglas Corporation 

Advisory Panel to Building Research Division 

Dr. Robert A. Hechtman, McLean, Virginia, Chairman 
Prof. Ray Clough, University of California 
Mr. Edward N. Davis, Underwriters Laboratories, Inc. 
Dr. J. Vincent Fitzgerald, Tile Council of America, Inc. 

Dr. William H. Lindsay, Jr., Mechanical Contractors Association of Phila- 
delphia, Inc. 
Mr. Andrew R. Lolli, State Department of General Services 
Mr. Raymond C. Reese, Toledo, Ohio 

Dean Charles E. Schaffner, Polytechnic Institute of Brooklyn 
Dr. J. A. Stavrolakis, American Standard 
Mr. Herbert H. Swinburne, Nolan, Swinburne & Associates 
Mr. Charles H. Topping, E. I. DuPont de Nemours & Company 

Advisory Panel to Electronic Technology Division 

Dr. Leon Podolsky, Pittsfield, Massachusetts, Chairman 

Mr. J. A. Caffiaux, Electronic Industries Association 

Mr. Ralph E. Clarridge, IBM Corporation 

Mr. Ivan G. Easton, General Radio Company 

Mr. H. J. Luer, Bell Telephone Laboratories 

Mr. Peter R. Perino, Statham Instruments, Inc. 

Dr. Robert Pritchard, Stanford University 

Mr. Robert I. Scace, General Electric Company 

Mr. Samuel H. Watson, Radio Corporation of America 

Dr. Richard C. Webb, Colorado Instruments, Inc. 

Advisory Panel to Technical Analysis Division 

Prof. Philip Morse, Massachusetts Institute of Technology, Chairman 
Prof. George B. Dantzig, Stanford University 
Mr. Leslie C. Edie, The Port of New York Authority 
Mr. Martin L. Ernst, Arthur D. Little, Inc. 
Mr. David B. Hertz, McKinsey and Company, Inc. 
Dr. William Linvill, Stanford University 
Dr. Hugh J. Miser, Hartford, Connecticut 
, Prof. Thornton L. Page, Houston, Texas 
Dr. George Pettee, Research Analysis Corporation 
Prof. Gustave J. Rath, Northwestern University 
Mr. Robert H. Shatz, United Aircraft 

Advisory Panel to Center for Computer Sciences and Technology 

Dr. Jack Moshman, LEASCO Systems & Research Corporation, Chairman 
Mr. H. G. Asmus, American Federation of Information Processing Societies 
Mr. T. E. Climis, IBM Corporation 

194 



Dr. William W. Eaton, Washington, D.C. 

Mr Elmer C. Kubie, Computer Company, Inc. 

Mr. J. Don Madden, Association for Computing Machinery 

Dr. Alan J. Rowe University of Southern California 

Mr. F. Gordon Smith, Business Supplies Corporation of America 

Dr. Willis H. Ware, The RAND Corporation 

A dvisory Panel to Center for Radiation Research 

Dr. Marshall R. Cleland, Chairman, Radiation Dynamics, Inc. 

Dr. S. C. Abrahams, Bell Telephone Laboratories 

Dr. Peter T. Demos, Massachusetts Institute of Technology 

Dr. R. B. Leachman, Kansas State University 

Prof. E. W. Montroll, University of Rochester 

Dr. Charles J. Mullin, University of Notre Dame 

Dr. George F. Pieper, National Aeronautics and Space Admin. 

Dr. W. C. Roesch, Battelle-Northwest 

Prof. Erwin F. Schrader, Case Institute of Technology 

Prof. C. G. Shull, Massachusetts Institute of Technology 



AWARDS AND HONORS 

Recognition of the Bureau's contributions to science and technology often 
takes the form of awards and honors from Government, academic, professional, 
and industrial groups. The following list reflects such recognition bestowed on 
Bureau staff members during fiscal year 1969. 



Recipient 
Astin, Allen V. 



Bates, Roger G. 
Bennett, John 
Branscomb, Lewis M. 
Brauer, Gerhard M. 
Foster, Bruce E. 

Jacox, Marilyn E. 
Lloyd, Edward C. 

Lonnie, Mansfield (retired) 

Marton, Ladislaus L. 

Meinke, W. Wayne 

Meyerson, Melvin R. 
Milligan, Dolphus E. 
Napolitano, Albert 



Award 

Elected Honorary Member, American Society 
of Heating, Refrigerating and Air Condition- 
ing Engineers 

Elected Member, National Academy of Public 
Administration 

American Chemical Society Award in Analyti- 
cal Chemistry 

George Kimball Burgess Award, Washington 
Chapter of American Society for Metals 

Career Service Award, National Civil Service 
League 

Souder Award of the International Association 
for Dental Research 

Henry L. Kennedy Award of American Con- 
crete Institute 

Frank E. Richart Award, American Society for 
Testing and Materials 

Recognition Award, Washington Academy of 
Sciences 

Awarded Fellow Member Certificate by Wash- 
ington Section, American Society of Mechan- 
ical Engineers 

Awarded Plaque from Mail Order Association 
of America for work on standards of cloth- 
ing sizes 

Elected Fellow, Institute of Electrical and 
Electronics Engineers 

Honorary Membership, Electron Probe Anal- 
ysis Society of America 

George von Hevesy Award, Journal of Radio- 
analytical Chemistry 

Special Award from American Nuclear Society 

Elected Honorary Member, Society Analytical 
Chemistry, Great Britain 

Burgess Memorial Award, Washington Chap- 
ter, American Society of Metals 

Recognition Award, Washington Academy of 
Sciences 

Elected Fellow, American Ceramic Society 



195 



Paffenbarger, George C. 

Parsons, Douglas E. (retired) 

Taylor, John K. 

Wildhack, William A. 

Williams, Morgan L. 

Burdick, Milton D. 
Coriell, Sam R. 
Currie, Lloyd A. 
Dibeler, Vernon H. 
Franklin, Alan D. 
Hamer, Walter J. 
Isbell, Horace S. 
LaFleur, Philip D. 
Meinke, W. Wayne 
Pope, Chester I. 
Scribner, Bourdon F. 
Sorrows, Howard E. 
Steiner, Bruce W. 



Gold Medal, Pierre Fouchard Academy 

Elected Honorary Fellow, International 
College of Dentists 

Distinguished Service Award, Underwriters' 
Laboratories, Inc. 

Awarded Honor Scroll, Washington Chap- 
ter, American Institute of Chemists 

Honorary Membership, Instrument Society 
of America 

District Meritorious Certificate Award by 
American Welding Society 



Elected Fellow, Washington Chapter of the 
American Institute of Chemists 



EUGENE C. CRITTENDEN AWARD 

(National Bureau of Standards) 



For superior performance by support personnel. 



Recipient 
Hester, James 
Hydro, John, Jr. 
Lantz, Herman L. 
Lederer, Grace S. 
Mayers, Susan B. 
Michalak, John L. 
Pittman, Arthur, Jr. 
Schneider, Lawrence 



Area 
Electrical services 
Glassblowing 
Floor care 

Procurement services 
Cleaning services 
Structural testing 
Payroll problems 
Precision instruments 



SAMUEL WESLEY STRATTON AWARD 

(National Bureau of Standards) 

For outstanding scientific engineering achievements in support of the NBS 
mission. 

David R. Lide, Jr. 

EDWARD BENNETT ROSA AWARD 

(National Bureau of Standards) 

For outstanding achievement in the development of standards of practice, the 
standards by which industry judges its operations, its production processes, 
and the quality of its products. 

W. Wayne Meinke 



196 



DEPARTMENT OF COMMERCE EXCEPTIONAL 
SERVICE AWARDS 

(Gold Medal) 



Recipient 
Costrell, Louis 
Kostkowski, Henry 
Kushner, Lawrence 
Lide, David R., Jr. 
Shuler, Kurt E. 
Group Award : 
Muehlhause, Carl 
Landon, Harry H. 
Carter, Robert S. 



O. 
Jr. 



Technical Area 
Radiation Physics Instrumentation 
Radiation Thermometry 
Research Management 
Molecular Structure 
Chemical Physics 

Nuclear Radiation 



DEPARTMENT OF COMMERCE MERITORIOUS 
SERVICE AWARDS 

(Silver Medal) 



Recipient 
Allen, David W. 
Coates, Clarence N., Jr. 
Cullen, William C. 
Cuthill, John R. 
DeVoe, James R. 
Garfinkel, Samuel B. 
Heinrich, Kurt F. J. 
McCrackin, Frank L. 
Marshak, Harvey 
Martin, William C, Jr. 
Oser, Hans J. 
Schooley, James F. 
Tilley, William R. 
Walton, William W. 
Weiss, Andrew W. 
Wollin, Harold F 
Joint Award : 

Shields, William R. 

Murphy, Thomas J. 



Technical Area 
Atomic Frequency and Time Standards 
Legislative Programs 
Materials Durability 
Alloy Physics 
Radiochemical Analysis 
Radioactivity Standards 
X-ray Spectrometry 
Ellipsometry 
Cryogenic Physics 
Atomic SpectrO'SCOpy 
Systems Dynamics 
Cryogenic Physics 
Technical Information 
Building Research 
Plasma Spectroscopy 
Weights and Measures 

Analytical Mass Spectrometry 



DEPARTMENT OF COMMERCE SUPERIOR 
SERVICE AWARDS 

(Bronze Medal) 



Recipient 
David, Richard M. 
Garing, Herbert H. 
Henley, Elizabeth L. M. 
Ledford, Albert E., Jr. 
Lunsford, Katherine S. 
Massie, Minnie R. 
Missimer, Joshua K. 
Pearson, Cornelius H. 
Peterson, Ruth L. 
Roberts, Marlon S. 
Snyder, Wilbert F. 
Williams, Earl S. 



Technical Area 
Radiation Chemistry 
Instrument Shops 
Administrative Issuance Systems 
Molecular Energy Levels 
Thermometer Calibration 
Thermometer Calibration 
Fibrous Systems 
Thermophysical Properties 
Spectroscopy 

Employee Development and Relations 
Radio Standards Engineering 
Electrical Instruments 



197 



EDUCATION, TRAINING, AND UNIVERSITY LIAISON 

A comprehensive employee development program, ranging from broad surveys 
to very detailed treatment of a new or specialized area of research, is available 
to all staff members and to members of other Government agencies and industrial 
personnel on a space-available basis. Courses and seminars are implemented 
primarily through the NBS Graduate School and special educational programs 
for subprofessional and non-professional employees, through non-Government 
educational and training facilities, and through interagency offerings. The 
programs range from adult basic education through postdoctoral research, and 
are offered at both the Boulder and Gaithersburg Laboratories. The primary 
objectives are to increase employee knowledge, skills, and efficiency in assigned 
duties in the categories more fully described below, and to prepare Bureau staff 
members to respond to the rapidly changing technology at all levels. Programs 
also include emphasis on maintaining liaison with the public, industry, com- 
merce, and science. 

In accord with Federal policy the Bureau is increasing its participation in 
projects aimed at stimulating community interest. Instruction by our scientists 
in the fields of their expertise, and facilities are being made available to the 
universities, public schools, professional societies, and the industrial and scien- 
tific community. In addition to numerous seminars offered through the Graduate 
School program and in cooperation with other Government and industrial 
agencies at the division and institute levels, there is the weekly National Bureau 
of Standards Scientific Colloquium at which current topics of broad interest to 
the Bureau are presented. These are open to the public and are attended by 
members of the university, industrial and Government communities, as well as 
by NBS personnel. Speakers are drawn from the outside community and from 
the NBS staff. Monthly colloquia under the joint sponsorship of the National 
Institutes of Health and the National Bureau of Standards are also offered, 
with each institution alternating as host. 

NBS Graduate School 

The NBS Graduate School curriculum includes graduate and undergraduate 
courses in the physical sciences, mathematics and specialized branches of engi- 
neering. A series of scientific colloquia and seminars designed to update and 
continue the education of the postdoctoral scientist are led by research leaders 
from the Bureau and from other research centers and universities. In addition, 
general staff development courses are offered, such as Supervision and Manage- 
ment, Reading Improvement, Technical Report Writing, and administrative 
and clerical conferences, workshops, and courses. 

Two special programs, designed for technicians and subprofessional laboratory 
personnel, offer courses both in-house and in cooperation with the Montgomery 
Junior College leading to two NBS Technician Certificates and/or the A. A. 
degree at the Montgomery Junior College. Surveys periodically redetermine 
course offerings and keep the program in ster> with the changes and variations 
in educational requirements and the changing technology. Graduate degrees 
based partly on credit obtained for courses or thesis research carried on under 
the NBS Graduate School Program have been earned by 2 Bureau employees 
this year, bringing the total to 350 graduate degrees earned at 45 different 
universities since the establishment of the educational program in 1908. 

The Graduate School at Boulder is associated with the University of Colorado 
in a Joint-Course program and Adjunct Professor Plan. Various graduate depart- 
ments of the NBS Graduate School at Boulder and the University offer courses 
which mutually benefit the Government and the University. 

Postdoctoral Research Associateships 

The National Bureau of Standards, in cooperation with the National Re- 
search Council, National Academy of Sciences-National Academy of Engineer- 
ing, offers a number of awards for postdoctoral research. 

These awards provide young scientists of unusual ability and promise an 
opportunity for fundamental research in various branches of the physical, engi- 
neering, and mathematical sciences. Applications are evaluated by a Board of 
Selection appointed by the National Research Council. The NRC-NBS Post- 
doctoral Research Associateship program has been in existence since 1954. 
There have been 187 awards made during these years. 

198 



Postdoctoral Research Associates on Duty During Fiscal Year 1969 



Name 
Alderman, Donald W. 
Bielefeld, Michael J. 
Borie, Edith F. 
Cahill, Kevin E. 
Davis, Douglas 
DeLancey, George B. 
Denenstein, Arnold M. 
Duerst, Richard W. 
Ensign, Thomas C. 
Epstein, Gabriel L. 
Fickett, Frederick R. 
Gibson, Benjamin F. 
Golub, Stephen 
Greenhouse, Jeffrey A. 
Handy, Larry B. 
Hegstrom, Roger A. 
Hoegy, Walter R. 
Knoeck, John W. 
Latanision, Ronald M. 
Ledbetter, Hassell M. 
Ott, William R. 
Parke, William C. 
Pierce, Stephen J. 
Plummer, Earl W. 
Ponzini, Robert G. 
Raveche, Harold J. 
Searles, Stuart K. 
Shirk, James S. 
Stokowski, Stanley E. 
Sullivan, Donald B. 
Thornton, Donald D. 
Weisman, Irwin I. 
Williams, H. T. 
Zalewski, E. F. 



University 
Cornell University 
U. of Pennsylvania 
U. of North Carolina 
Harvard University 
U. of Florida 
U. of Pittsburgh 
U. of Pennsylvania 
U. of California (Berkeley) 
U. of Wyoming 
U. of California (Berkeley) 
Oregon State University 
Stanford University 
Columbia University 
U. of California (Berkeley) 
U. of Wisconsin 
Harvard University 
U. of Michigan 
Iowa State University 
Ohio State University 
U. of Illinois 
U. of Pittsburgh 
George Washington University 
U. of Calif. (Santa Barbara) 
Cornell University 
Michigna State University 
U. of California (LaJolla) 
U. of Alberta (Canada) 
U. of California (Berkeley) 
Stanford University 
Vanderbilt University 
Syracuse University 
U. of California (Berkeley) 
U. of Virginia 
U. of Chicago 



NBS Adviser 
R. J. Mahler 
J. J. Spijkerman 
L. C. Maximon 
S. Meshkov 
H. Okabe 
H. Oser 

F. K. Harris 

G. F. Kokoszka 
T. Chang 

J. Reader 
R. Powell 
M. Danos 
B. Steiner 
W. J. Lafferty 
F. E. Brinckman 
J. H. Shirley 
R. Mountain 
J. K. Taylor 
A. W. Ruff 
R. P. Reed 
W. Wiese 
R. W. Hayward 
M. Newman 
R. D. Young 
S. Meshkov 
R. Mountain 
P. Ausloos 

A. M. Bass 

L. H. Grabner 
R. A. Kamper 

B. M. Mangum 
L. H. Bennett 
M. Danos 

R. A. Keller 



Other Employee Development Programs 

In addition to the programs for technicians described above, the National 
Bureau of Standards recognizes the need to develop and upgrade the non- 
professional staff, which plays an essential role in the support of the scientific 
staff. Therefore, courses in adult basic education are offered in cooperation with 
the Montgomery County Public Schools, designed to help the individual in his 
work. Also, foreign-born individuals who need improvement in oral and written 
English can enroll in classes being taught by experienced adult teachers who are 
aware of the problems facing the non-English speaking individual. 

Non-Government Education 

Non-Government education falls into three categories . . . full-time (3 to 12 
months) graduate study and research assignments at universities and research 
centers; full-time (less than 3 months) attendance at institutes, seminars, short 
concentrated courses and workshops ; and part-time, job-related academic courses 
at universities and in industry. In the last year 654 staff members at Washington 
and Boulder were trained through non-Government facilities, and 6 career 
employee were selected for full-time graduate study or research assignments 
at universities and research centers. Participants in approved full-time train- 
ing programs receive full salary and expenses, including tuition, fees, travel, 
and per diem, as well as transportation of family and household effects. In 
addition, 648 staff members, mostly from technical divisions, attended job- 
related courses on a semester basis, and shorter concentrated courses at uni- 
versities and in industry. 



199 



Interagency Training 

Courses made available through the Interagency Training Programs are an 
additional effective means of improving program operations for NBS personnel. 
Courses are offered at Government facilities in Supervision, Management, Office 
Skills and Practices, and specialized programs. This pooling of agency resources 
offers broader employee development opportunities at a saving to the Govern- 
ment. During 1968, 230 National Bureau of Standards employees took advan- 
tage of the interagency offerings. 

PUBLICATIONS* 
PUBLICATIONS IN THE BUREAU'S SERIES 

During the year NBS publications totaled 1058 published papers 
and documents. 

Of the formal publications, 98 appeared in the Journal of Research, 
and 676 in the journals of professional and scientific societies. Also, 
172 summary articles were presented in the Bureau's Technical News 
Bulletin. 

In the non-periodical series, 112 documents were published: 8 in 
the Monograph series, 2 in the Handbook series, 28 in the Special Pub- 
lication series, 6 in the Building Science series, 50 in the Technical Note 
series, 7 in the National Standard Reference Data Series, 1 in the Ap- 
plied Mathematics series, 9 in the Federal Information Processing 
Standard series, and 1 in the Product Standards series. 

Journal of Research. Reports National Bureau of Standards research and devel- 
opment in physics, mathematics, chemistry, and engineering. Comprehensive 
scientific papers give complete details of the work, including laboratory data, 
experimental procedures, and theoretical and mathematical analyses. Illus- 
trated with photographs, drawings, and charts. 

Section A. Physics and Chemistry. Issued six times a year. Annual subscription : 
Domestic, $9.50; foreign, $11.75. Single copy price varies. SD Catalog No. 
C13.22/sec.A :74. 

Section B. Mathematical Sciences. Issued quarterly. Annual subscription: Domes- 
tic, $5 ; foreign, $6.25. Single copy, $1.25. SD Catalog No. C13.22/sec.B :74. 

Section C. Engineering and Instrumentation. Issued quarterly. Annual subscrip- 
tion : Domestic, $5 ; foreign, $6.25. Single copy, $1.25. S.D. Catalog No. C13.22/ 
sec.C :74. 

Journal of Research 
Section A. Physics and Chemistry 

J. Res. Nat. Bur. Stand. (U.S.), 72A (Phys. and Chem.), No. 4 (July-August 
1968) 

Mass spectrometry study of photolonization. X. Hydrogen chloride and methyl 
halides. Morris Krauss, James A. Walker, and Vernon H. Dibeler. 

The fourth and fifth spectra of vanadium (Viv and Vv). Laura Iglesias. 

Variation of absorptance-curve shape with changes in pigment concentration. 
Gerald L. Howett. 

Periodic acid, a novel oxidant of polycyclic aromatic hydrocarbons. Alexander J. 
Fatiadi. 



♦Publications for which a price is indicated are available by purchase from the Superin- 
tendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 (foreign 
postage, one-fourth additional). The NBS non-periodical series are also available from the 
Clearinghouse for Federal Scientific and Technical Information, Springfield, Va. 22151. 
Reprints from outside journals and the NBS Journal of Research may often be obtained 
directly from the authors. 

200 



A galvanic cell with a low emf-temperature coefficient. Gerald N. Roberts and 

Walter J. Hamer. 
Synthesis of cerite. Jun Ito. 
Tables of collision integrals for the (m, 6) potential function for 10 values of m. 

Max Klein and Francis Smith. 
Spectrum of relaxation times in GeOa glass. A. Napolitano and P. B. Macedo. 
Resume of values of the Faraday. Walter J. Hamer. 

J. Res. Nat. Bur. Stand. (U.S.), 72A (Phys. and Chem.), No. 5 (September- 
October 1968). 

Studies in bomb calorimetry. A new determination of the energy of combustion 

of benzoic acid in terms of electrical units. K. L. Churney and G. T. Armstrong. 
Effect of low pressures on the room temperature transitions of polytetrafluoro- 

ethylene. G. M. Martin and R. K. Eby. 
Electrostatic potentials and their spatial derivatives about point defects in 

ionic crystals. Herbert S. Bennett. 
Electric fields produced by a charge density in ionic crystals. Herbert S. Bennett. 
Mass speetrometric study of the photoionization of some fluorocarbons and 

trifluoromethyl halides. Clemente Juan Noutary. 
Infrared matrix spectra of lithium fluoride. Stanley Abramowitz, Nicolo Asquista, 

and Ira W. Levin. 
Electronic transition moment integrals for first ionization of CO and the A-X 

transition in CO + . Some limitations on the use of the r-centroid approximation. 

Paul H. Krupenie and William Benesch. 
The configurations 3d n 4p in doubly ionized atoms of the iron group. C. Roth. 
Electron impact excitation of hydrogen Lyman-a radiation. Robert L. Long, Jr., 

Donald M. Gox, and Stephen J. Smith. 

J. Res. Nat. Bur. Stand. (U.S.), 72A (Phys. and Chem.), No. 6 (November- 
December 1968. 

Interaction energy surfaces for Li(2 2 S) and Li(2 2 P) with H 2 M. Krauss. 
Energy levels and classified lines in the first spectrum of technetium (Tci). 

W. R. Bozman, C. H. Corliss, and J. L. Tech. 
The first spectrum of tungsten ( W i) . Donald D. Laun and C. H. Corliss. 
Theoretical interpretation of the even levels in the first spectrum of tungsten. 

Y. Shadmi and E. Caspl. 
Stable carbon isotope ratio measurement with a gas density meter. S. P. Wasik 

and W. Tsang. 
The single crystal spectrum of hexakis( imidazole) nickel (II) nitrate. Curt W. 

Reimann. 
Crystalline alpha and beta forms of 3-O-a-D-glucopyranosyl-D-arabinopyranose. 

Horace S. Isbell, Harriet L. Frush, and J. D. Moyer. 
Preparation and solubility of hydroxyapatite. E. C. Moreno, T. M. Gregory, and 

W. E. Brown. 
High temperature dehydroxylation of apatitic phosphates. T. Negas and R. S. 

Roth. 

J. Res. Nat. Bur. Stand. (U.S.), 73A (Phys. and Chem.), No. 1 (January- 
February 1969) 

Specific heats of oxygen at coexistence. Robert D. Goodwin and Lloyd A. Weber. 

Specific heats C v of fluid oxygen from the triple point to 300 K at pressures 
to 350 atmospheres. Robert D. Goodwin and Lloyd A. Weber. 

Thermodynamic properties of fluid oxygen at temperatures to 250 K and pres- 
sures to 350 atmospheres on isochores at 1.3 to 3.0 times critical density. 
Robert D. Goodwin. 

Two new standards for the pH scale. Bert R. Staples and Roger G. Bates. 

Calculation of diffusion coefficients in ternary systems from diaphragm cell 
experiments. P. R. Patel, E. C Moreno, and T. M. Gregory. 

Calculated line strength for the transition array (3<Z 3 -f 3# 2 4s)-3(Z 2 4p in Tin. 
H. Mendlowitz. 

Morphological stability of a cylinder. Sam R. Coriell and Stephen C. Hardy. 

Distorted tetahedra in strontium copper akermanite. Jun Ito and H. Steffen 
Peiser. 

201 



Tritium-labeled compounds XII. Note on the synthesis of D-glucose-2-£ and 
D-mannose-2-£. Horace S. Istoell, Harriet L. Frush, C. W. R. Wade, and A. J. 
Fatiadi. 

A Survey of blemishes on processed microfilm. C. S. McCamy, S. R. Wiley, and 
J. A. Speckman. 

J. Res. Nat. Bur. Stand. (U.S.), 73A (Phys. and Chem.), No. 2 (March-April 
1969) 

Color representation of electron microprobe area-scan images by a color sepa- 
ration process. Harvey Yakowitz and Kurt F. J. Heinrich. 
Configurations 3cZ"4p in singly ionized atoms of the iron group. C. Roth. 

Configurations 3(ZMp+3tf w_1 4s4p in Sc n, Ti n, and V 11. C. Roth. 
Effective interactions in the even configurations of the third spectra of the iron 

group. Y. Shadmi, E. Caspi, and J. Oreg. 
Test of a kinetics scheme : Emission in H ( 2 S ) 4- NO ( 2 II ) . M. Krauss. 
A nuclear magnetic resonance and relaxation study of dimethoxyborane. T. C. 

Farrar and T. Tsang. 
The effects of low energy irradiation on organometallics. Organometal halides 

of group IVA. F. E. Brinckman, Gerald F. Kokoszka, and Norman K. Adams. 

Jr. 
Measurements of gaseous diffusion coefficients by a gas chromotographic 

technique. S. P. Wasik and K. E. McCulloh. 
Phase relations in the Ru-Ir-0 2 system in air. C. L. McDaniel and S. J. Schneider. 
Heats of reaction of natural rubber with sulfur. Norman Bekkedahl and James 

J. Weeks. 
A tahle of rotational constants of symmetric top molecules giving rise to 

microwave spectra. Matthew S. Lojko and Yardley Beers. 
Energy levels, wave functions, dipole and quadrupole transitions of Fe +++ ions 

in sapphire. Jacques Lewiner and Paul H. E. Meijer. 

J. Res. Nat. Bur. Stand. (U.S.) 73A (Phys. and Chem.), No. 3 (May-June 
1969) 

New even levels and classified lines in the first spectrum of tungsten (W 1) 

C. H. Corliss. 
The heat of combustion of beryllium in fluorine. K. L. Churney, and G. T. 

Armstrong. 
Deuterium isotope effect on the dissociation of weak acids in water and deuterium 

oxide. R. A. Robinson, Maya Paabo, and Roger G. Bates. 
Vortex motions in ideal Bose superfluid. Martin J. Cooper. 
Franck-Condon factors for the ionization of H 2 and D 2 0. R. Botter and H. M. 

Rosenstock. 
Topological features of hot carrier induced anisotropic breakdown on silicon 

diode surfaces. George G. Harman. 
The third spectrum of praseodymium (Pr. in) in the vacuum ultraviolet. Jack 

Sugar. 

Section B. Mathematical Sciences 
J. Res. Nat. Bur. Stand. (U.S.), 72B (Math. Sci.), No. 3 (July-September 1968) 

Interaction in multidimensional contingency tables : An information theoretic 

approach. H. H. Ku and S. Kullback. 
On the coupling of longitudinal and transverse waves in a linear three-element 

viscoelastic string subjected to transverse impact. Jack C. Smith and Jeffrey 

T. Fong. 
Allocating service periods to minimize delay time. W. A. Horn. 
The second orthogonality conditions in the theory of proper and improver 

rotations. I. Derivation of the conditions and of their main consequences. 

Harry Gelman. 
Thickness and connectivity in graphs. Arthur M. Hobbs and J. W. Grossman. 

J. Res. Nat. Bur. Stand. (U.S.), 72B (Math. Sci.), No. 4 (October-December 

1968). 

Principal submatrices VII : Further results concerning matrices with equal 

principal minors. R. C. Thompson. 
On the multipliers of the Dedekind modular function. Joseph Lehner. 

202 



Minimax error selection of a discrete univariate distribution with prescribed 

componentwise bounds. A. J. Goldman and P. R. Meyers. 
Minimax error selection of a discrete univariate distribution with prescribed 

componentwise ranking. A. J. Goldman. 
On the signs of the v -derivatives of the modified Bessel functions J (a?) and 

K (x),T>. O. Reudink. 
Comparison of finite-difference computations of natural convection. K. E. 

Torrance. 
Generalized inverses and solutions of linear systems. John Z. Hearon. 

J. Res. Nat. Bur. Stand. (U.S.), 73B (Math. Sci.), No. 1 (January-March 
1969) 

A table of integrals of the error functions. Edward W. Ng and Murray Geller. 
Fourier coefficients of Mathieu functions in stable regions. Henning Friichting. 
A note on the T-transformation of Lubkin. W. D. Clark, H. L. Gray, and J. E. 

Adams. 
The cylinder problem in thermoviscoelasticity. Warren S. Edelstein. 
Relations within sequences of congruential pseudo-random numbers. Peter H. 

Verdier. 
On the mean dimensions of restricted random walks. Peter H. Verdier and 

Edmund A. DiMarzio. 
The cube of every connected graph is 1-hamiltonian. Gary Chartrand and S. F. 

Kapoor. 
Minimum-length covering by intersecting intervals. W. A. Horn. 

J. Res. Nat. Bur. Stand. (U.S.), 73B (Math. Sci.), No. 2 (April- June 1969) 

An evaluation of linear least squares computer programs. Roy H. Wampler. 

The traffic assignment problem for a general network. Stella C. Dafermos and 
Frederick T. Sparrow. 

Sufficient conditions for the instability of numerical integration methods. Abbas J. 
Abdel Karim. 

The second orthogonality conditions in the theory of proper and improper rota- 
tions. II. The intrinsic vector. Harry Gelman. 

The second orthogonality conditions in the theory of proper and improper rota- 
tions. III. The conjugacy theorem. Harry Gelman. 

Subgroups of SL(t,z). Morris Newman. 

Cuttable and cut-reducible matrices. Rosalind B. Marimont. 

Automorphic integrals with preassigned periods. Joseph Lehner. 

A digital computer technique for calculating the step response of lumped or 
distributed networks. James R. Andrews and N. S. Nahman. 

Symmetry and the crossing number for complete graphs. Thomas L. Saaty. 

Section C. Engineering and Instrumentation 

J. Res. Nat. Bur. Stand. (U.S.), 72C (Engr. and Instr.), No. 3 (July-September 
1968) 

Gas density balance design considerations. E. C. Creitz. 

Standard mismatch — the production of controlled small reflections in wave- 
guides. L. Lewin. 

Viscoelastic behavior of dental amalgam. P. L. Oglesby, G. Dickson, M. L. Rod- 
riguez, R. M. Davenport, and W. T. Sweeney. 

The steady-state creep behavior of dental amalgam. George Dickson, Philip 
Oglesby, and Ruth Davenport. 

J. Res. Nat. Bur. Stand. (U.S.), 72C (Engr. and Instr.), No. 4 (October- 
December 1968) 

Theoretical and experimental study on longitudinal impact of tapered rods. 
L. R. Hettche. 

Analytical studies of probe conduction errors in ground temperature measure- 
ments. B. A. Peavy. 

Nonlinear constrained optimization by a nonrandom complex method R. A. 
Mitchell and K. L. Kaplan. 

375-572^-70 14 203 



J. Res. Nat. Bur. Stand. (U.S.), 73C (Engr. and Instr.), Nos. 1 and 2 (January- 
June 1969) 

An interferometer for measuring gradients in both refractive index and thickness 

of large or small optics. J. B. Saunders. 
A Kerr electro-optical technique for observation and analysis of high-intensity 

electric fields. Esther C. Cassidy and Harold N. Cones. 
Student-* deviate corresponding to a given normal deviate. Brian L. Joiner. 
A heat loss compensated calorimeter and related theorems. Steve R. Domen. 
Laboratory measurements of air cavity temperature in a passenger car tire. 

B. G. Simson and J. Mandel. 

Technical News Bulletin. The best single source of information concerning 
the Bureau's research, developmental, cooperative and publications activities, 
this monthly publication is designed for the industry-oriented individual whose 
daily work involves intimate contact with science and technology — for engineers, 
chemists, physicists, research managers, product-development managers, and com- 
pany executives. Readers use the TNB to learn of new developments with 
practical applications, to fill in background, to get ideas for further investiga- 
tions, and for information on NBS calibration services, publications, and con- 
ferences. Annual Subscription : Domestic, $3 ; foreign, $4. Single copy price 30 
cents. Available on a 1-, 2-, or 3-year subscription basis. SD Catalog No. 013.13 :54. 

Monographs. Major contributions to the technical literature on various subjects 
related to the Bureau's scientific and technical activities. 

Monogr. 25, Section 6. Standard x-ray diffraction powder patterns, Section 6. — 
Data for 60 substances, H. E. Swanson, H. F. McMurdie, M. C. Morris, and 
E. H. Evans, Nat. Bur. Stand. (U.S.), Monogr. 25, Sec. 6, 101 pages (June 
1968). 60 cents. 

Monogr. 70, Volume III. Microwave spectral tables. Volume III. Polyatomic mole- 
cules with internal rotation, P. F. Wacker, M. S. Cord, D. G. Burkhard, J. D. 
Petersen, and R. F. Kukol, Nat. Bur. Stand. (U.S.), Monogr. 70, Vol. Ill, 275 
pages (June 1969). $4.25. 

Monogr. 70, Volume IV. Microwave spectral tables. Volume IV. Polyatomic mole- 
cules without internal rotation, M S. Cord, J. D. Petersen, M. S. Lojko, and 
R. H. Haas, Nat. Bur. Stand. (U.S.), Monogr. 70, Vol. IV, 429 pages (Oct. 1968). 
$5.50. 

Monogr. 70, Volume V. Microwave spectral tables. Volume V. Spectral line list- 
ing, M. S. Cord, M. S. Lojko, and J. D. Petersen, Nat. Bur. Stand. (U.S.), 
Monogr. 70, Vol. V, 538 pages (June 1968). $4.75. 

Monogr. 105. Acid-based behavior in aprotic organic solvents, M. M. Davis, Nat. 
Bur. Stand. (U.S.), Monogr. 105, 156 pages (Aug. 1968). $2.25. 

Monogr. 107. Acceleration due to gravity at the National Bureau of Standards, 
D. R. Tate, Nat. Bur. Stand. (U.S.), Monogr. 107, 24 pages (June 1968). 25 
cents. 

Monogr. 109. Investigations of the exploding wire process as a source for high 
temperature studies, E. C. Cassidy, S. Abramowitz, and C. W. Beckett, Nat. 
Bur. Stand. (U.S.), Monogr. 109, 53 pages (Nov. 1968). 55 cents. 

Monogr. 111. Technology of liquid helium, R. H. Kropschot, B. W. Birmingham, 
and D. B. Mann, Editors, Nat. Bur. Stand. (U.S.), Monogr. Ill, 380 pages 
(Oct. 1968). $2.00. 

Handbook. Recommended codes of engineering and industrial practice {in- 
cluding safety codes) developed in cooperation with interested industries, pro- 
fessional organizations, and regulatory todies. In many cases the recommended 
requirements are given official status through their incorporation in local or- 
dinances by State and municipal regulatory bodies. 

H105-1. Specifications and tolerances for reference standards and field standard 
weights and measures. 1. Specifications and tolerances for field standard 
weights, T. M. Stabler, Editor, Nat. Bur. Stand. (U.S.), Handb. 105-1, 10 pages 
(Apr. 1969). 25 cents. 

H106. CODASYL COBOL journal of development 1968, Nat. Bur. Stand. (U.S.), 
Handb. 106, 344 pages (July 1969). $2.75. 

204 



Special Publications. (Formerly Miscellaneous Publications) This series in- 
cludes proceedings of high-level national and international conferences sponsored 
by NBS, precision measurement and calibration volumes, NBS Research High- 
lights, and other special publications appropriate to this grouping, such as admin- 
istrative pamphlets, wall charts and bibliographies. 

SP236, 1968 Edition. Services provided by NBS standard frequency stations 
WWV, WWVH, WWVB, and WWVL, Nat. Bur. Stand. (U.S.), Spec. Publ. 236, 

15 pages (1968). (Supersedes Misc. Publ. 236, 1967 edition.) 

SP236, 1969 Edition. NBS frequency and time broadcast services, radio stations 
WWV, WWVH, WWVB, and WWVL, Nat. Bur. Stand. (U.S.), Spec. Publ. 236, 

16 pages (1969). 25 cents. (Supersedes Spec. Publ. 236, 1968 edition.) 
SP260-16. Standard reference materials: homogeneity characterization of NBS 

spectrometric standards IV: preparation and microprobe characterization of 

W-20% Mo alloy fabricated by powder metallurgical methods, H. Yakowitz, 

R. E. Michaelis, and D. L. Vieth, Nat. Bur. Stand. (U.S.), Publ. 260-16, 30 pages 
(Jan. 1969). 35 cents. 
SP296. Mass transport in oxides. Proceedings of a symposium held at the Na- 
tional Bureau of Standards, Gaithersburg, Md., October 22-25, 1967, J. B. 

Wachtman, Jr. and A. D. Franklin, Editors, Nat. Bur. Stand. (U.S.), Spec. 

Publ. 296, 224 pages (Aug. 1968). $3.00. 
SP298. Quantitative electron probe microanalysis. Proceedings of a Seminar held 

at the National Bureau of Standards, Gaithersburg, Md., June 12-13, 1967, 

K. F. J. Heinrich, Editor, Nat. Bur. Stand. (U.S.), Spec. Publ. 298, 305 pages 

(Oct. 1968). $3.00. 
SP299, Volumes 1 and 2. Neutron cross sections and technology. Proceedings 

of a conference held in Washington, D.C., March 4-7, 1988, D. T. Goldman, 

Editor, Nat. Bur. Stand. (U.S.), Spec. Publ. 299, Vol. 1, 660 pages and Spec. 

Publ. 299, Vol. 2, 718 pages (Sept. 1968). $10.50 per set of 2 volumes. 
SP300, Volume 1, Precision measurement and calibration. Selected NBS papers 

on statistical concepts and procedures, H. H. Ku, Editor, Nat. Bur. Stand. 

(U.S.), Spec. Publ. 300, Vol. 1, 436 pages (Feb. 1969). $5.50. 
SP300, Volume 2. Precision measurement and calibration temperatures. Selected 

NBS papers on temperature, J. F. Swindells, Editor, Nat. Bur. Stand. (U.S.), 

Spec. Publ. 300, Vol. 2, 520 pages (Aug. 1968). $4.75. 
SP300, Volume 3. Precision measurement and calibration. Selected NBS papers 

on electricity — low frequency, F. L. Hermach and R. F. Dziuba, Editors, Nat. 

Bur. Stand. (U.S.), Spec. Publ. 300, Vol. 3, 498 pages (Dec. 1968). $4.50. 

( Supersedes in part Handbook 77, Vol. I. ) 
SP301. Molecular dynamics and structure of solids. Proceedings of the Second 

Materials Research Symposium held at the National Bureau of Standards, 

Gaithersburg, Md., October 16-19, R. S. Carter and J. J. Rush, Editors, Nat. 

Bur. Stand. U.S.), Spec. Publ. 301, 580 pages (June 1969). $4.00. 
SP302. Thermal conductivity. Proceedings of the seventh conference held at the 

National Bureau of Standards, Gaithersburg, Md., November 13-16, 1967, D. R. 

Flynn and B. A. Peavy, Jr., Editors, Nat. Bur. Stand. (U.S.), Spec. Publ. 302, 

820 pages ( Sept. 1968) . $6.25. 
SP303. Mechanical and thermal properties of ceramics. Proceedings of a sym- 
posium held at Gaithersburg, Md., April 1-2, 1968, J. B. Wachtman, Jr., Editor, 

Nat. Bur. Stand. (U.S.), Spec. Publ. 303, 275 pages (May 1969). $4.25. 
SP304. The modernized metric system— The International System of Units (SI), 

Nat. Bur. Stand. (U.S.), Spec. Publ. 304, 1 chart (1988). 50 cents. (Supersedes 

Misc. Publ. 232.) 
SP304A. Brief history and use of the English and metric system of measure- 
ment, Nat. Bur. Stand. (U.S.), Spec. Publ. 304A, 4 pages (1968). 20 cents. 
SP305. Publications of the National Bureau of Standards 1966-1S67, B. L. Ober- 

holtzer, Nat. Bur. Stand. (U.S.), Spec. Publ. 305, 221 pages (Apr. 1969). $2.00. 
SP306-1. Bibliography on the analyses of optical atomic spectra. Section 1. 

"H-^V, C. E. Moore, Nat. Bur. Stand. (U.S.), Spec. Publ. 306-1, Sec. 1, 89 pages 

(Sept. 1968). $1.00. 
SP306-2. Bibliography on the analyses of optical atomic spectra. Section 2. 

24 Cr- 41 Nb, C. E. Moore, Nat. Bur. Stand. (U.S.), Spec. Publ. 306-2, Sec. 2, 63 

pages (Feb. 1969). 60 cents. 
SP306-3. Bibliography on the anlyses of optical atomic spectra. Section 3. 

42 Mo- 57 La and 72 Hf- 89 Ac, C. E, Moore, Nat. Bur. Stand. (U.S.), Spec. Publ. 306-3, 

Sec. 3, 37 pages (May 1969) . 50 cents. 

205 



SP307. Wolf-Rayet stars. Proceedings of a symposium held at the Joint Institute 
for Laboratory Astrophysics, University of Colorado, Boulder, Colo., June 10- 
14, 1968, K. M. Grebbe and R. N. Thomas, Editors, Nat. Bur. Stand. (U.S.), 
Spec. Publ. 370, 286 pages (Dec. 1968) . $3.00. 

SP308. Technical highlights of the National Bureau of Standards, Annual Report 
Fiscal Year 1968, Nat. Bur. Stand. (U.S.), Spec. Publ. 308, 216 pages (Nov. 
1968). 

SP309, Volume 2. Computer literature bibliography 1964-1967, W. W. Youden, 
Nat. Bur. Stand. (U.S.), Spec. Publ. 309, Vol. 2, 385 pages (Dec. 1968). $5.00. 

SP310. Nuclear standards for chemistry and technology. Proceedings of a Sym- 
posium on Standards in Nuclear Chemistry and Technology held at the 156th 
National Meeting of the American Chemical Society, Atlantic City, N.J., Sep- 
tember 8-9, 1968, H. F. Beeghly, J. P. Cali, and W. W. Meinke, Editors, Nat. 
Bur. Stand. (U.S.), Spec. Publ. 310, 261 pages (Dec. 1968). $1.25. 

SP311. Report of the 53d National Conference on Weights and Measures, 1968, 
R. L. Koeser, Editor, Nat. Bur. Stand. (U.S.), Spec. Publ. 311, 182 pages (Mar. 
1969). $1.25. 

SP312, Volumes I and II. Modern trends in activation analysis. Proceedings of 
the 1968 International Conference held at the National Bureau of Standards, 
Gaithersburg, Md., October 7-11, 1968, J. R. DeVoe, Editor and P. D. LaFleur, 
Assistant Editor, Nat. Bur. Stand. (U.S.), Spec. Publ. 312, Vol I, 691 pages 
and Vol. II, 676 pages (June 1969). $8.50 per set of 2 volumes. 

SP313. Making valuable measurements. Proceedings of the 1968 Standards Lab- 
oratory Conference, H. L. Mason, Editor, Nat. Bur. Stand. (U.S.), Spec. Publ. 
313, 177 pages (May 1969). $1.50. 

SP315. Bibliography on the high temperature chemistry and physics of mate- 
rials, October, November, December 1968, J. J. Diamond, Editor, Nat. Bur. 
Stand. (U.S.), Spec. Publ. 315, 72 pages (Jan. 1969). 70 cents. 

SP315-1. Bibliography on the high temperature chemistry and physics of mate- 
rials, January, February, March 1969, J. J. Diamond, Editor, Nat. Bur. Stand. 
(U.S.), Spec. Publ. 315-1, 81 pages (April 1969). 75 cents. 

SP316. Hydraulic research in the United States, 1968, G. Kulin, Editor, Nat. Bur. 
Stand. (U.S.), Spec. Publ. 316, 331 pages (June 1969). $2.50. 

National Standard Reference Data Series. Includes the evaluated reference 
data and critical reviews of long-term interest that are produced by data centers 
within the NSRDS network. The National Standard Reference Data System is 
a Government-wide effort to provide the U.S. technical community with effective 
access to the quantitative data of physical science, critically evaluated and com- 
piled for convenience. 

NSRDS-NBS15. Molten salts: Volume 1. Electrical conductance, density, and 
viscosity data, G. J. Janz, F. W. Dampier, G. R. Lakshminarayanan, P. K. 
Lorenz, and R. P. T. Tomkins, Nat. Stand. Ref. Data Ser., Nat. Bur. Stand. 
(U.S.), 15, 145 pages ( Oct. 1968 ) . $3.00. 

NSRDS-NBS19. Thermodynamic properties of ammonia as an ideal gas, L. Haar, 
Nat. Stand. Ref. Data Ser., Nat. Bur. Stand. (U.S.), 19, 13 pages (Aug. 1968). 
20 cents. 

NSRDS-NBS20. Gas phase reaction kinetics of neutral oxygen species, H. S. 
Johnston, Nat. Stand. Ref. Data Ser., Nat. Bur. Stand. (U.S.), 20, 54 pages 
(Sept. 1968). 45 cents. 

NSRDS-NBS24. Theoretical mean activity coefficients of strong electrolytes in 
aqueous solutions from to 100 °C, W. J. Hamer, Nat. Stand. Ref. Data Ser., 
Nat. Bur. Stand. (U.S.), 24, 276 pages (Dec. 1968). $4.25. 

NSRDS-NBS25. Electron impact excitation of atoms, B. L. Moiseiwitsch and 
S. J. Smith, Nat. Stand. Ref. Data Ser., Nat. Bur. Stand. (U.S.), 25, 120 pages 
(Aug. 1968). $2.00. 

NSRDS-NBS26, Ionization potentials, appearance potentials, and heats of 
formation of gaseous positive ions, J. L. Franklin, J. G. Dillard, H. M. Rosen- 
stock, J. T. Herron, K. Draxl, and F. H. Field, Nat. Stand. Ref. Data Ser., 
Nat. Bur. Stand. (U.S.), 26, 289 pages (June 1969). $4.00. 

NSRDS-NBS27. Thermodynamic properties of argon from the triple point to 
300 K at pressures to 1000 atmospheres, A. L. Gosman, R. D. McCarty, and 
J. G. Hust, Nat. Stand. Ref. Data Ser., Nat. Bur. Stand. (U.S.), 27. 151 nases 
(Mar. 1969). $1.25. S 

Building Science Series. Disseminates technical information developed at the 
Bureau on building materials, components, systems, and whole structures. The 

206 



series presents research results, test methods, and performance criteria related 
to the structural and environmental functions and the durability and safety 
characteristics of building elements and systems. 

BSS14. Experimental determination of eccentricity of floor loads applied to a 
bearing wall, D. Watstein and P. V. Johnson, Nat. Bur. Stand. (U.S.), Bldg. Sci. 
Series 14 (June 1968). 15 cents. 

BSS15. Interrelations between cement and concrete properties. Part 4. Shrink- 
age of neat portland cement pastes and concretes. (Contains section 9 and 
section 10.) R. L. Blaine, H. T. Ami, and D. N. Evans, Nat. Bur. Stand. (U.S.), 
Bldg. Sci. Series 15, Part 4, 79 pages (Mar. 1969) . 75 cents. 

BSS16. Techniques for the survey and evaluation of live floor loads and fire 
loads in modern office buildings, J O. Bryson and D. Gross, Nat. Bur. Stand. 
(U.S.), Bldg. Sci. Series 16, 32 pages (Dec. 1968). 40 cents. 

BSS17. Causes of variation in chemical analyses and physical tests of portland 
cement, B. L. Bean and J. R. Dise, Nat. Bur. Stand. (U.S.), Bldg. Sci. Series 
17, 34 pages (Mar. 1969). 40 cents. (Supersedes Monograph 28.) 

BSS18. Smoke and gases produced by burning aircraft interior materials, D. 
Gross, J. J. Loftus, T. G. Lee, and V. E. Gray, Nat. Bur. Stand. (U.S.), Bldg. 
Sci. Ser. 18, 29 pages (Feb. 1969). 35 cents. 

BSS19. A study of the variables involved in the saturating of roofing felts, S. H. 
Greenfeld, Nat. Bur. Stand. (U.S.), Bldg. Sci. Ser. 19, 18 pages (June 1969). 
30 cents. 

Applied Mathematics Series. Mathematical tables, manuals, and studies of 
special interest to physicists, engineers, chemists, biologists, mathematicians, 
computer programmers, and others engaged in scientific and technical work. 
Some of the volumes are reissues of the Mathematical Tables prepared by the 
Project for the Computation of Mathematical Tables conducted by the Works 
Projects Administration for the City of New York under the scientific sponsor- 
ship of NBS. 

AMS60. Matrix representations of groups, M. Newman, Nat. Bur. Stand. (U.S.), 
Appl. Math. Series 60, 82 pages (July 1968). 60 cents. 

Federal Information Processing Standards Publications. (FIPS PUBS) The 
publications in this series collectively constitute the Federal Information Process- 
ing Standards Register. The purpose of the Register is to serve as the official 
source of information in the Federal Government regarding (1) uniform Fed- 
eral information processing standards resulting from provisions of Public Law 
89-306 (the Brooks Bill) and (2) data elements and codes standards in data 
systems developed under the provisions of Bureau of the Budget Circular No. 
A-86. FIPS PUBS will include approved Federal information processing stand- 
ards information of general interest, and a complete index of relevant standards 
publications. 

FIPS PUB 0. General description of Federal Information Processing Standards 
register, H. S. White, Jr., Editor, Nat. Bur. Stand. (U.S.), Fed. Info. Process. 
Stand. Publ. (FIPS Pub.) 0, 8 pages (Nov. 1, 1968). 20 cents. 

FIPS PUB 1. Code for information interchange. Hardware standard inter- 
change codes and media, H. S. White, Jr., Editor, Nat. Bur. Stand. (U.S.), Fed. 
Info. Process. Stand. Publ. (FTPS Pub.) 1, 4 pages (Nov. 1, 1968). 10 cents. 

FIPS PUB 2. Perforated tape code for information interchange. Hardware 
standard interchange codes and media, H. S. White, Jr., Editor, Nat. Bur. 
Stand. (U.S.), Fed. Info. Process. Stand. Publ. (FIPS Pub.) 2, 4 pages (Nov. 1, 
1968). 10 cents. 

FIPS PUB 3. Recorded magnetic tape for information interchange (800 CPI, 
NRZI). Hardware standard interchange codes and media, H. S. White, Jr., 
Editor, Nat. Bur. Stand. (U.S.), Fed. Info. Process. Stand. Publ. (FIPS Pub.) 
3, 4 pages (Nov. 1, 1968). 10 cents. 

FIPS PUB 4. Calendar date (Federal general data standard representations 
and codes), H. S. White, Jr., Editor, Nat. Bur. Stand. (U.S.), Fed. Info. 
Process. Stand. Publ. (FIPS Pub.) 4, 4 pages (Nov. 1, 1968). 20 cents. 

FIPS PUB 5. States of the United States (Federal general data standard rep- 
resentations and codes), H. S. White, Jr., Editor, Nat. Bur. Stand. (U.S.), 
Fed. Info, Process. Stand. Publ. (FIPS Pub.) 5, 4 pages (Nov. 1, 1968). 20 
cents. 

207 



FIPS PUB 6. Counties of the States of the United States (Federal general data 
standard representations and codes), H. S. White, Jr., Editor, Nat. Bur. Stand. 
(U.S.), Fed. Info. Process. Stand. Publ. (FIPS Pub.) 6, 32 pages (Nov. 1, 
1968). 40 cents. 

FIPS PUB. 7. Implementation of the code for information interchange and 
and related media standards. Hardware standards interchange codes and 
media, H. S. White, Jr., Editor, Nat. Bur. Stand. (U.S.), Fed. Info. Process. 
Stand. Publ. (FIPS Pub.) 7, 14 pages (Mar. 7, 1969). 25 cents. (Supplement to 
FIPS Publ. 1 through 3.) 

FIPS Pub. 8. Metropolitan statistical areas. Federal general data standard rep- 
resentations and codes, H. S. White, Jr., Editor, Nat. Bur. Stand. (U.S.), Fed. 
Info. Process. Stand. Publ. (FIPS Pub.) 8, 8 pages (June 9, 1969). 20 cents. 

Product Standards. This series comprises voluntary standards that establish 

(1) dimensional requirements for standard sizes and types of various products; 

(2) technical requirements for the product and (3) methods of testing grading, 
and marking these products. The objective is to define requirements for products 
in accordance with the principal demands of the trade. 

PS9-68. Fabrics for book covers, J. Eisele, Technical Standards Coordinator, 
Nat. Bur. Stand. (U.S.), Prod. Stand. 9-68, 13 pages (Apr. 1968). 10 cents. 
( Supersedes Commercial Standard OS 7-40. ) 

Technical Notes. Designed to supplement the Bureau's regular publications 
program, Technical Notes provide a publication medium for communications and 
reports on data of limited or transitory interest. They often serve as final reports 
on work at NBS sponsored by other Government agencies. 

TN366. An analysis of the Brayton cycle as a cryogenic refrigerator, R. C. 

Muhlenhaupt and T. R. Strobridge, Nat. Bur. Stand. (U.S.), Tech. Note 366, 

116 pages (Aug. 1968). $1.25. 
TN367. A bibliography of thermophysical properties of methane from to 

300 °K, L. A. Hall, Nat. Bur. Stand. (U.S.), Tech Note 367, 121 pages (May 

1968). 60 cents. 
TN368. Solution of the Abel integral transform for a cylindrical luminous 

region with optical distortions at its boundary, E. R. Mosburg, Jr., and M. S. 

Lojko, Nat. Bur. Stand. (U.S.), Tech. Note 368, 27 pages (July 12, 1968). 

25 cents. 
TN369. Interferometric measurements of the complex dielectric constant of 

liquids, W. S. Lovell and L. M. Thiel, Nat. Bur. Stand. (U.S.), Tech. Note 369, 

89 pages (Aug. 1968). 50 cents. 
TN370. Calibration principles and procedures for field strength meters (30 Hz 

to 1 GHz), H. E. Taggart and J. L. Workman, Nat. Bur. Stand. (U.S.), Tech. 

Note 370, 157 pages (Mar. 1969). $1.25. 
TN371. Transistorized low voltage regulator circuits and design, J. H. Rogers, 

Nat. Bur. Stand. (U.S.), Tech. Note 371, 38 pages (Sept. 1968). 30 cents. 
TN372. Mathematical techniques for EPR analysis of S=5/2 ions in C 2 sym- 
metry. Application to Fe 3+ in quartz, R. L. Petersen, L. M. Matarrese, and J. S. 

Wells, Nat. Bur. Stand. (U.S.), Tech. Note 372, 23 pages (June 1969). 35 cents. 
TN373. Radio-frequency measurements in the NBS Institute for Basic Stand- 
ards, R. S. Powers and W. F. Snyder, Editors, Nat. Bur. Stand. (U.S.), Tech. 

Note 373, 116 pages (June 1969) . $1.00. 
TN374. Incipient and developed cavitation in liquid cryogens, D. K. Edmonds 

and J. Hord, Nat. Bur. Stand. (U.S.), Tech. Note 374, 31 pages (Feb. 1989). 

35 cents. 
TN375. Tables of bias functions, Bi and B 2 for variances based on finite samples 

of processes with power law spectral densities, J. A. Barnes, Nat. Bur. Stand. 

( U.S. ) , Tech. Note 375, 39 pages ( Jan. 1969) . 50 cents. 
TN377. Slush hydrogen fluid characterization and instrumentation, C. F. Sindt, 

P. R. Ludtke, and D. E. Daney, Nat, Bur. Stand. (U.S.), Tech. Note 377, 69 

pages (Feb. 1939). 65 cents. 
TN378. Preparation and characterization of slush hydrogen and nitrogen gels, 

A. S. Raplal and D. E. Daney, Nat. Bur. Stand. (U.S.), Tech. Note. 378, 43 

pages (May 1969). 50 cents. 
TN432. Connection tables from Wiswesser chemical structure notation — a par- 
tial algorithm, G. F. Fraction, J. C. Walker, and S. J. Tauber, Nat. Bur. Stand. 

( U.S. ) , Tech. Note. 432, 63 pages ( Sept. 1968) . 65 cents. 

208 



TN433. Input/output packages for the systems 360 assembly language processor, 

P. A. D. deMaine, Nat. Bur. Stand. (U.S.), Tech. Note 433, 14 pages (Sept. 

1968). 25 cents. 
TN436. Studies of calibration procedures for load cells and proving rings as 

weighing devices, G. B. Anderson and R. C. Raybold, Nat. Bur. Stand. (U.S.), 

Tech. Note 436, 22 pages (Jan. 1969) . 30 cents. 
TN441. Tabulation of published data on Soviet electron devices through Octo- 
ber 1967, C. P. Marsden, Nat. Bur. Stand. (U.S.), Tech. Note 441, 98 pages 
(July 1968) . 55 cents. ( Supersedes Technical Note 265. ) 
TN444. Reform: a general-purpose program for manipulating formatted data 

files, R. McClenon and J. Hilsenrath, Nat. Bur. Stand. (U.S.), Tech. Note 444, 

28 pages (Aug. 1968) . 40 cents. 
TN447. Research on high temperature materials at the National Bureau of 

Standards, E. Passaglia, Editor, Nat. Bur. Stand. (U.S.), Tech. Note 447, 19 

pages (July 1968) . 20 cents. 
TN451. Radiochemical Analysis Section: summary of activities July 1967 to 

June 1968, J. R. DeVoe, Editor, Nat. Bur. Stand. (U.S.), Tech. Note 451, 131 

pages (Jan. 1989). $1.25. 
TN452. Activities of the NBS Spectrochemical Analysis Section July 1967 

through June 1968, B. F. Scribner, Editor, Nat. Bur. Stand. (U.S.), Tech. Note 

452, 80 pages ( Sept. 1968). $1.00. 
TN453. Elecrochemical Analysis Section: summary of activities July 1967 to 

June 1968, R. G. Bates, Editor, Nat. Bur. Stand. (U.S.), Tech. Note 453, 88 

pages (July 1968). 55 cents. 
TN454. Analytical Coordination Chemistry Section : summary of activities July 

1967 to June 1968, O. Menis, Editor, Nat. Bur. Stand. (U.S.), Tech. Note 454, 

92 pages (July 1968). 55 cents. 
TN 455. Microchemical Analysis Section : summary of activities July 1967 to 

June 1968, J. K. Taylor, Editor, Nat. Bur. Stand. (U.S.), Tech. Note 455, 145 

pages (Oct. 1968). $1.25. 
TN456. Analytical Mass Spectrometry Section : summary of activities July 1967 

to June 1968, W. R. Schields, Editor, Nat. Bur. Stand. (U.S.), Tech. Note 456, 54 

pages (Nov. 1968). 55 cents. 
TN457. Organic Chemistry Section: summary of activities July 1967 to June 

1968, R. Schaffer, Editor, Nat. Bur. Stand. (U.S.), Tech. Note 457, 127 pages 

(Sept. 1968). $1.25. 
TN458. Activation Analysis Section: summary of activities July 1967 to June 

1968, P. D. LaFleur, Editor, Nat. Bur. Stand. (U.S.), Tech. Note 458, 109 pages 

(Mar. 1969). $1.00. 
TN459. Separation and Purification Section : summary of activities July 1967 to 

June 1968, D. H. Freeman, Editor. Nat. Bur. Stand. (U.S.), Tech. Note 459, 56 

pages (Dec. 1968). 60 cents. 
TN461. Tables of solutions to Bragg's equation for copper, cobalt, iron, and 

chromium Ka~ radiation and small diffraction angles, J. P. Colson and E. S. 

Clark, Nat. Bur. Stand. (U.S.), Tech. Note 461, 75 pages (Aug. 1968). 50 cents. 
TN462, Nonnumeric data processing in Europe : a field trip report, M. E. Stevens, 

Nat. Bur. Stand. (U.S.), Tech. Note 462, 66 pages (Nov. 1968). 65 cents. 
TN463. Mossbauer effect study of magnetic ordering in copper-rich Cu-Ni-Fe 

alloys, L. J. Swartzendruber, Nat. Bur. Stand. (U.S.), Tech. Note 463, 138 

pages (Aug. 1968). 25 cents. 
TN464. The NBS Alloy Data Center : function, bibliographic system, related data 

centers and reference books, G. C. Carter, L. H. Bennett, J. R. Cuthill, and 

D. J. Kahn, Nat. Bur. Stand. (U.S.), Tech. Note 464, 199 pages (Aug. 1968). 

$1.25. 
TN465. Measurement of carrier liftime in semiconductors — an annotated bibli- 
ography covering the period 1949-1967, W. M. Bullis, Nat. Bur. Stand. (U.S.), 

Tech. Note 465, 64 pages (Nov. 1968) . 60 cents, 
TN466. Matching fingerprints by computer, J. H. Wegstein, J. F. Rafferty, and 

W. J. Pencak, Nat. Bur. Stand. (U.S.), Tech. Note 466, 17 pages (July 1968). 

20 cents. 
TN467, Part 1. Activation analysis : a bibliography, G. J. Lutz, R. J. Boreni, R. 

S. Maddock, and W. W. Meinke, Editors, Nat. Bur. Stand. (U.S.), Tech. Note 

467, Part 1, 520 pages (Sept. 1968). $6,50. Part 1 is sold only with Part 2. 
TN467, Part 2. Appendices. Activation analysis : a bibliography, G. J. Lutz, R. J. 

Boreni, R. S. Maddock, and W. W. Meinke, Editors, Nat. Bur. Stand. (U.S.), 

Tech. Note 467, Part 2, 197 pages (Sept. 1968). $6.50. Part 2 is sold onlv with 

Part 1. 

209 



TN469. NBS interagency transducer project, P. S. Lederer, Nat. Bur. Stand. 

(U.S).. Tech. Note 469, 23 pages (Oct. 1968). 30 cents. 
TN470 Edpac : utility programs for computer-assisted editing, copy-production, 

and retrieval, C. G. Messina and J. Hilsenrath, Nat. Bur. Stand. (U.S.), Tech. 

Note 470, 80 pages ( Jan. 1969) . 75 cents. 
TN472 Methods of measurement for semiconductor materials, process control, 

and devices. Quarterly report July 1 to September 30, 1968, W. M. Bullis, 

Editor, Nat. Bur. Stand. (U.S.), Tech. Note 472, 45 pages (Dec. 1968). 

TN473 Laboratory-field comparison of built-up roofing membranes, T. H. Boone, 
L. F. Skoda, and W. G. Cullen, Nat. Bur. Stand. (U.S.), Tech. Note 473, 15 
pages (Dec. 1968). 25 cents. 

TN474 Critically evaluated transition probalities for Ea I and II, B. M. Miles 
and W. L. Wiese, Nat. Bur. Stand. (U.S.), Tech. Note 474, 22 pages (Jan. 1969). 
30 cents. , L . _ , 1 

TN475 Methods of measurement for semiconductor materials, process control, 
and devices. Quarterly report October 1 to December 31, 1968, W. M. Bulks, 
Editor, Nat. Bur. Stand. (U.S.), Tech. Note 475, 38 pages (Feb. 1969). 45 

TN476 Line emission sources for concentration measurements and photochemis- 
try, W. Braun and T. Carrington, Nat. Bur. Stand. (U.S.), Tech. Note 476, 23 
pages ( Mar. 1969 ) . 30 cents. 

TN477 The performance of roofing made with Asplund felts, S. H. Greenfeld, 
Nat." Bur. Stand. (U.S.), Tech. Note 477, 27 pages (Mar. 1969). 35 cents. _ 

TN478, Some evolving conventions and standards for character information 
coded in six, seven, and eight bits, J. L. Little, Nat. Bur. Stand. (U.S.), Tech. 
Note 478, 30 pages (May 1969) . 35 cents. 

TN479. A Fortran program for analysis of ellipsometer measurements, F. L. 
McCrackin, Nat. Bur. Stand. (U.S.), Tech. Note 479, 82 pages (Apr. 1969). 75 
cents. 

TN480. Misalinement detector for axial loading fatigue machines, D. C. Robin- 
son, Nat. Bur. Stand. (U.S.), Tech. Note 480, 15 pages (Apr. 1969). 25 cents. 

TN481. A semi-automated single fingerprint identification system, J. H. Weg- 
stein, Nat. Bur. Stand. (U.S.), Tech. Note 481, 21 pages (Apr. 1969). 30 cents. 

TN482. Superconductive materials and some of their properties, B. W. Roberts, 
Nat. Bur. Stand. (U.S.), Tech. Note 482, 129 pages (May 1969). $1.25. 

TN483. Construction and operation of a simple high-precision copper-point 
blackbody and furnace, R. D. Lee, Nat. Bur. Stand. (U.S.), Tech. Note 483, 16 
pages (May 1969) . 30 cents. 

TN484. A review of rate constants of selected reactions of interest in re-entry 
flow fields in the atmosphere, M. H. Bortner, Nat. Bur. Stand. (U.S.), Tech. 
Note 484, 62 pages (May 1969) . 60 cents. 

PUBLICATIONS IN OUTSIDE JOURNALS 

Abrams, M. D., A comparative sampling of the systems for producing computer- 
drawn flow charts, Proc. 1968 ACM National Comf., Las Vegas, Nev., Aug. 27- 
29, 1968, pp. 743-750 (Brandon/Systems Press Inc., Princeton, N.J., 1968). 

Acquista, N., Abramowitz, S., Lide, D. R., Structure of the alkali hydroxides. II. 
The infrared spectra of matrix isolated CsOH and OsOD, J. Chem. Phys. 49, 
No. 2, 780-782 (July 15, 1968). 

Ahearn, A. J., Paulsen, P. J., Workshop on mass spectrometric analysis of solids 
at the National Bureau of Standards in Gaithersburg, Md., Nov. 18 and 19, 
1968, Anal. Chem. 41, No. 2, 79A-81A (February 1969) . 

Allan, D. W., Guetrot, A., Higbie, L. S., Lavaneeau, J. D., An application of 
statistical smoothing techniques on VLF signals for comparison of time be- 
tween USNO and NBS, Proc. 23rd Frequency Control Symp., Atlantic City, 
N.J., May 6-8, 1969, p. 248 (1969). 

Altschuler, H. M., Comments on An improved method for measuring scattering 
parameters of nonreciproeal two-ports, IEEE Trans. Microwave Theory Tech. 
MTT-16, No. 4, 261-262 (April 1968). 

Alvarez, R., Paulsen, P. J., Kelleher, D. E., Simultaneous determination of trace 
elements in platinum by isotope dilution and spark source mass spectrometry, 
Anal. Chem. 41, No. 7, 955-958 (June 1969). 

Amona, T., Saito, S., Hirota, E., Morino, Y. Johnson, D. R., Powell, F. X., Micro- 
wave spectrum of the CIO radical, J. Mol. Spectry. 30, No. 2, 275-289 (May 



210 



Ambler, E., Schooley, J. F., Colwell, J. H., Pfeiffer, E. R., Frederikse, H. R., 
Hosier, W. R., Tliurber, W. R., Transition temperatures and critical fields of 
SrTiO a and mixed titanates, Proc. Xth Intern. Conf. Low Temperature Physics, 
Moscow, U.S.S.R., Aug. 31-Sept. 6, 1966, Vol. 2B, Superconductivity, Paper 
S123, 142-148 (1968). 

Anderson, H. J., Brenner, A., Preparation of rhenium hexafluoracetylacetonate, 
J. Electrochem. Soc. 116, No. 4, 513 (April 1969). 

Arenhovel, H., General formulas for describing the absorption of polarized pho- 
tons by oriented nuclei, Phys, Rev. 171, No. 4, 1212-1216 (July 20, 1968). 

Arenhovel, H., Danos, M., Baryon resonances in nuclei : Magnetic moment anom- 
aly in b H and 3 He, Physics Letters 28B, No. 5, 299-301 (Dec. 23, 1968). 

Arp, V., Properties and preparation of high-purity aluminum, Proc. 1968 Summer 
Study on Superconducting Devices and Accelerators, Brookhaven National 
Laboratory, Upton, N.Y., June 10-July 19, 1968, Part III, BNL 50155 (C-55), 
1095-1114 (Clearinghouse for Federal Scientific and Technical Information, 
Springfield, Va., April 1969, $3.00). 

Arp, V. D., Kasen, M. B., Reed, R. P., Magnetic energy storage and cryogenic 
aluminum magnets, Tech., Rept. AFAPL-TR-68-87, 122 pages (Air Force 
Systems Command, Wright-Patterson Air Force Base, Ohio, February 1969). 

Astin, A. V., Management and the metric system, Defense Management J. 5, No. 
2,27-34 (1969). 

Ausloos, P., Lias, S. G., Primary modes of decomposition of superexcited w-alkane 
molecules (Proc. Intern. Conf. Photochemistry, Munchen, Germany, Sept. 6-9, 
1967) , Ber. deut. Gunsenges. 72, No. 2, 187-195 (1968) . 

Ausloos, P., Rebbert, R. E., Lias, S. G., Gas-phase photolysis of cyclohexane in 
the photoionization region, J. Phys. Chem. 72, No. 11, 3904-3914 (October 
1968). 

Ausloos, P., Rebbert, R. E., Lias. S. G., Structure and reactivity of propyl ions 
in gas-phase radiolysis, J. Am. Chem. Soc. 90, No. 18, 5031-5033 (Aug. 28, 
1968). 

Averbuch, P., James, L. W., Mahler, R. J., Nuclear ultrasonic fase passage, Appl. 
Phys. Letters 11, No. 11, 339-340 (Dec. 1, 1967) . 

Bach, R. L., Caswell, R. S., Energy transfer to matter by neutrons, Radiation 
Res. 35, No. 1, 1-25 (July 1968). 

Barber, D. J., Tighe, N. J., Neutron damage in single crystal aluminum oxide, 
J. Am. Ceram. Soc. 51, No. 11, 611-617 (November 1968). 

Barger, R. L., Hall, J. L., Pressure shift and broadening of methane line at 3.39^ 
studied by laser-saturated molecular absorption, Phys. Rev. Letters 22, No. 1, 
4-8, (January 6, 1969). 

Bates, A. A., Responsibility in building research, Proc. Third Australian Build- 
ing Research Cong., Melbourne, Australia, August 1967, pp. 27-34 (1968). 

Bates, R. G., Equilibrium properties of acids and bases in amphibrotic mixed 
solvents (Proc. Symp. Equilibria and Reaction Kinetics in Hydrogen Bonded 
Solvent Systems, University of New Castle, Upon Tyne, England, Jan. 10^12, 
1968), Chapter in Hydrogen-Bonded Solvent Systems, A. K. Covington and 
P. Jones, Eds., pp. 49-86 (Taylor and Francis, London, England, 1968). 

Bates, R. G., Inner reference electrodes and their characteristics. Chapter in Glass 
Microelectrodes, M. Lavallee, O. F. Schanne, and N. C. Hebert, Eds., pp. 1-24 
(John Wiley & Sons, Inc., New York, N.Y., 1969) . 

Bates, R. G., Measurement of pH, Handbook of Biochemistry, H. A., Sober, ed., 
pp. J190-J194 (Chemical Rubber Company, Cleveland, Ohio, 1967). 

Bates, R. G., Medium effects and pH in nonaqueous solvents, C. D. Ritchie and 
J. F. Coetzee, Eds., pp. 45-96 (Marcel Dekker Inc., New York, N.Y., 1969). 

Bates, R. G., Measurement of pH, Handbook of Biochemistry, Ed. H. A. Sober, 
pp. J190-J194 (Chemical Rubber Company, Cleveland, Ohio, 1967). 

Bay, Z., Luther, G. C, Locking a laser frequency to the time standard, Appl. 
Phys, Letters 13, No. 9, 303-304 (Nov. 1, 1968) . 

Beatty, R. W., Discussion of effect of relizability conditions upon estimated 
limits of mismatch error in the calibration of fixed attenuators, IEEE Trans. 
Microwave Theory Tech. MTT-16, No. 11, 976 (November 1968). 

Beatty, R. W., Fentress, G. H, An attenuation and phase shift divider circuit, 
Proc. IEEE 56, No. 11, 2063-2064 (November 1968) . 

Beatty, R. W., Yates, B. C, A graph of return loss versus frequency for quarter- 
wavelength short-circuited waveguide impedance standards, IEEE Trans. 
Microwave Theory MTT-17, No. 5, 282-284 (May 1969) . 

Beatty, R. W., Coaxial power, impedance and attenuation calibration at the Na- 
tional Bureau of Standards, Microwave J. 11, No. 5, 65-75 (May 1968). 

211 



Bechtoldt, C. J., Ogburn, F., Smit, J. Structure and morphology of electro- 
deposited molybdenum dendrites, J. Electrochem. Soc. 115, No. 8, 814-816 
(August 1968). 

Beckett, C. W., Cezairliyan, A., High-speed thermodynamic measurements and 
related techniques, Chapter in Experimental Thermodynamics, J. P. McCul- 
lough and D. W. Scott, Eds., Vol. I, Oalorimetry of Non-reacting Systems, 
Chapt. 14, 551-585 (Butterworth and Co., London. England, 1968) „ 

Bekkedahl, N., Crystallization of natural rubber, Rev. Gen. Caoutchouc Plastiques 
45, No. 3, 341-6—463-9 (1968) . 

Bender, P. L., Optical orientation experiments at Princeton, Chapter in 
Polarisation Matiere et Rayonnement, Volume Jubilaire en L'Honneur 
D'Alfred Kastler, pp. 436^41 (Presses Universitaires de France, Paris, 
1969). 

Bender, P. L., Alley, C. O., Currie, D. G., Faller, J. E., Satellite geodesy 
using laser range measurements only, J. Geophys. Res. 73, No. 16, 5353-5358 
(Aug. 15, 1968). 

Bender, P. L., Branscomb, L. M., Credit for gravity apparatus, Phys. Today 
Letter 20, No. 10, 17 (October 1967). 

Bennett, H. S., Diffuse and propagating modes in the Heisenberg paramagnet, 
Phys. Rev. 174, No. 2, 629-639 (Oct. 10, 1968) . 

Bennett, H. S., Magnet scattering of neutrons from Heisenberg antiferro- 
magnets, J. Appl. Phys. 40, No. 3, 1552-1553 (Mar. 1, 1969). 

Bennett, H. S., Phenomenology of neutron scattering in Heisenberg systems, 
Phys. Rev. 176, No. 2, 650-654 (Dec. 10, 1968). 

Bennett, H. S., Ultrasonic attenuation in Heisenberg magnets, Phys. Rev. 181, 
No. 2, 978 (May 10, 1969). 

Bennett, J. A., The initiation of fatigue microcracks under sequential bending 
and torsional loads, Trans. ASM 61, No. 2, 210-218 (June 1968). 

Bennett, L. H., Nuclear magnetism, Chapter in Magnetism and Magnetic Mate- 
rials 1968 Digest, H. Chang and T. R. McGuire, Eds., Chapt. 14, pp. 201-221 
(Academic Press, Inc., New York, N.Y., 1968) . 

Bennett, L. H., Mebs, R. W., Watson, R. E., Solute Knight shifts in noble metals, 
Phys. Rev. 171, No. 3, 611-626 (July 15, 1968). 

Bennett, L. H., Swartzendruber, L. J., Some comments on "The corrosion of 
materials in desalination plants", Desalination 4, 389-390 (1968). 

Berger, M. J., Seltzer, S. M., Chappell, S. E., Humphreys, J. C, Motz, J. W., 
Response of silicon detectors to monoenergetic electrons with energies be- 
tween 0.15 and 5.0 MeV, Nucl. Instr. Methods 69, No. 2, 181-193 (April 1969). 

Berman, H. A., West, E. D., Heat capacity of liquid nitromethane from 35° to 
200°C, J. Chem. Eng. Data 14, No. 1, 107-109 (January 1969). 

Birmingham, B. W., Ed., A report on the 1967 Applied Superconductivity Con- 
ference, Cryogenics 8, No. 3, 176-179 (June 1968). 

Birmingham, B. W., Flynn, T. W., Cryogenics in United States National Programs, 
Cryogenics 9, No. 1, 3-10 (February 1969). 

Birmingham, B. W., Flynn, T. M., National programs and the compressed gas 
industry (Proc. 55th Annual Meeting of the Compressed Gas Association, 
New York, N.Y., Jan. 1968), Chapter in The Future of the Compressed Gas 
Industry, pp. 39^-49 (Compressed Gas Assoc. Inc., New York, N.Y., 1969). 

Blandford, J. M., Bensing, P. L., Book, Testing Programs for the Apparel In- 
dustry. Evaluation of Material and Components, Part I, 31 pages ; Part II, 222 
pages (Apparel Research Foundation, Inc., Washington, D.C., Oct. 1, 1968). 

Blandford, J. M., NBS-ARF apparel materials testing and evaluation project, 
Second Annual Conf. Apparel Research Foundation, Washington, D.C., Oct. 7-9, 
1968, 4 pages (Apparel Research Foundation, Washington, D.C., 1968). 

Boone, T. H., Skoda, L. F., Cullen, W. C, Laboratory-field comparisons of 
built-up roofing membranes, Roofing Siding Insul. Mag. 46, No. 4, 28-33 
(April 1969). 

Botter, R, Rosenstock, H. M., Franck-Condon factors for NH 3 and H 2 0, Chapter 
in Advances in Mass Spectrometry 4, 579-589 (Institute of Petroleum, London, 
England, 1968). 

Boutillon, M., Henry, W. H., Lamperti, P. J., Comparison of exposure standards 
in the 10-50 kV X-ray region, Metrologia 5, No. 1, 1-11 (January 1969). 

Bowen, R. L., Cleek, G. W., X-ray-opaque reinforcing fillers for composite mate- 
rials, J. Dental Res. 48, No. 1, 79-82 (January-February 1969). 

Bowen, R. L., Paffenbarger, G. C, Mullineaux, A. L., A laboratory and clinical 
comparison of silicate cements and a direct-filling resin: A progress report, 
J. Prosthetic Dentistry 20, No. 5, 426-437 (November 1968) . 

212 



Bowen, R. L., Mullineaux, A. L., Adhesive restorative materials, Dental Abstr. 
14, No. 80, 80-82 (February 1969) . 

Boyd, M. E., Larsen, S. Y., Kilpatrick, J. E., Quantum mechanical second virial 
coefficient of a Lennard-Jones Gas. Helium, J. Chem. Phys. 50, No. 9, 4034-4055 
(May 1,1969). 

Branscomb, L. M., Joint Institute for Laboratory Astrophysics of the National 
Bureau of Standards and the University of Colorado, Boulder, Colo., observa- 
tory report, Bull. Am. Astron. Soc. 1, No. 1, 27-33 (January 1969) . 

Branscomb, L. M., Physics and the nation in a crystal ball, Phys. Today 21, No. 8, 
23-28 (August 1968). 

Brauer, G. M., McLaughlin, R., Huget, E. F., Aluminum oxide as a reinforcing 
agent for zinc oxide-eugenol-o-ethoxybenzoic acid cements, J. Dental Res. 47, 
No. 4, 622-628 (July-August 1968). 

Brinckman, F. E., Gordon, G., Energetic intermediates in inorganic synthesis : 
characterization of transport species in electric discharge, Proc. Intern. Symp. 
Decomposition of Organometallic Compounds to Refractory Ceramics, Metals, 
and Metal Alloys, Dayton, Ohio, November 1967, pp. 29-46 (University of 
Dayton Press, Dayton, Ohio, October 1968). 

Broadhurst, M. G., The dielectric properties of leaves, sticks, and dirt at radio 
and microwave frequencies, Proc. 1968 Annual Report Conf. Electrical Insu- 
lation and Dielectric Phenomena, Oct. 21-23, 1968, Buck Hill Falls, Pa., 
pp. 146-152 (Natl. Acad. Sci.-Natl. Res. Council, Washington, D.C., 1969). 

Brockman, J. F., Popular science writing, Proc. 1967 Inst. Technical Industrial 
Communications, Colorado State University, Fort Collins, Colo., June 12-16, 
1967, pp. 96-100 (1967). 

Brooks, R., Horton, A. T., Torgesen, J. L, Occlusion of mother liquor in solution- 
growth crystals, J. Crystal Growth 2, 279-283 (1968). 

Brower, W. S., Robbins, C. R., Growth of CaTiSiOs by the Czochralski method, 
J. Crystal Growth 5, 233-234 (1969). 

Brown, P. J., Human factors research in motor vehicle occupant restraint sys- 
tems, IEEE Trans. Man-Machine Systems MMS-9, No. 3, 88-89 (September 
1969). 

Bullis, W. M., Measurement problems in microcircuit processing, (Proc. Gov- 
ernment Microcircuit Applications Conf., Gaithersburg, Md., Oct. 1-3, 1968), 
GOMAC Digest 1, 215-217 (Office of Naval Research, Washington, D.C., 
October 1968). 

Bullis, W. M., Brewer, F. H., Kolstad, C. D., Swartzendruber, L. J., Temperature 
coefficient of resistivity of silicon and germanium near room temperature, 
Solid-State Electron. 11, No. 7, 639-646 (July 1968). 

Bur, A. J., Roberts, D. E., Rodlike and random coil behavior of poly(w-butyl 
isocyanate) in dilute solution, Proc. 1968 Annual Report Conf. Electrical 
Insulation and Dielectric Phenomena, Oct. 21-23, 1968, Buck Hill Falls, Pa., 
pp. 17-21 (Natl. Acad. Sci.-Natl. Res. Council, Washington, DC., 1969). 

Burke, P. G., Cooper, J. W., Ormonde, S., Electron-impact excitation of n-2 
states in He, Phys. Rev. Letters 17, No. 7, 345-348 (Aug. 15, 1966). 

Cahill, K. E., Pure states and the P representation, Phys. Rev. 180, No. 5, 1239- 
1243 (Apr. 25, 1969). 

Cahill, K. E., Regularization of the P representation, Phys. Rev. 180, No. 5, 1244- 
1255 (Apr. 25, 1969)). 

Cameron, J. M., The statistical consultant in a scientific laboratory, Techno- 
metrics 11, No. 2, 247-254 (May 1969). 

Campbell, W. H., Aurora, Encyclopedia of Atmospheric Sciences and Astro- 
geology, R. W. Fairbridge, Ed., pp. 105-106 (Reinhold Publ. Co., New York, 
N.Y., 1967). 

Carter, G. C, The NBS Alloy Data Center, Mater. Res. Bull. 3, 919-922 (1968). 

Case, W. E., Harrington, R. D., Hysteresis effects in the slope calibration 
method for magnetometers, Proc. IEEE 56, No. 10, 1733-1734 (October 1968). 

Casella, R. C, Decay modes with coherent resonant-energy transfer between 
deep impurities in solids, Phys. Rev. 174, No. 3, 830-834 (October 15, 1968). 

Casella, R. C, Time reversal and the K° meson decays, I, Phys. Rev. Letters, 

21, No. 15, 1128-1131 (October 7, 1968). 

Casella, R. C, Time reversal and the K° meson decays. II. Phys, Rev. Letters 

22, No. 11, 554-556 (March 17, 1969). 

Cassel, J. M., Gallagher, J. Reynolds, J. A., Steinhardt, J., The role of transport 
ion binding studies of serum albumin, Biochemistry 8, No. 4, 1706-1713 (April 
1969). 

Cassel, J. M., Steinhardt, J., Limitations inherent in the Aph method of deter- 
mining binding isotherms of bovine serum albumin, Biochemistry 8, No. 6, 
2603-2609 (Jun* 1969). 

213 



Cassidy, E. 0., Abramowitz, S., Time-resolved emission and absorption studies 
of exploding wire spectra (Proc. 4th Conf. Exploding Wires, Boston, Mass., 
October 18-21, 1967), Book, Exploding Wires 4, 109-124 (Plenum Press Inc., 
New York, N.Y., 1968). 

Cassidy, E. C, Cones, H. N., Wunsch, D. C, Booker, S. R., Calibration of a 
Kerr cell system for high-voltage pulse measurements, IEEE Trans. Instr. 
Meas. IM-17, No. 4, 313-320 (December 1968). 

Champion, C. E., Marinenko, G., Errors in coulometric chloride titrations due 
to photodecomposition of silver chloride, Anal. Chem. 41, No. 1, 205-207 
(January 1969). 

Chang, S. S., Switch arrangement and power averaging in constant current 
calorimetric heating, Rev. Sci. Instr. 40, 822-825 (1969). 

Christ, B. W., Giles, P. M., On the detection of retained austenite in high-carbon 
steels by Fe 57 Mossbauer spectroscopy, with appendix, Trans. Met. Soc. 
AIME 242, 1915-1925 (September 1968). 

Christ, B. W., Smith, G. V., Effects of impurities on yield and flow strength of 
zone refined iron, Mem. Sci. Rev. Met. LXV, 208-223 (June 15, 1968). 

Chung, K., Danos, M., Huber, M. G., Microscopic description of the absorption 
of bound 7r-mesons, Physics Letters 29B, No. 5, 265-267 (May 26, 1969). 

Clark, A. F., Low temperature thermal expansion of some metallic alloys, Cryo- 
genics 8, No. 5, 282-289 (October 1968). 

Clark, A. F., Fickett, F. R., A nonsuperconducting detection system for low 
level dc voltages, Rev. Sci Instr. 40, No. 3, 465^t68 (March 1969). 

Clark, A. F., Powell, R. L., Longitudinal magnetoresistance of pure single-crystal 
copper, Phys. Rev. Letters 21, No. 12, 802-804 (September 16, 1968). 

Clark, H. E., Young, R. D., Field emission through single strontium atoms 
adsorbed on a tungsten surface, Surface Sci. 12, 385-389 (1968). 

Cole, A. R. H., Lafferty, W. J., Thibault, R. J., Rotational fine structure of the 
perpendicular band, v- t , of ethane, J. Mol. Spectry. 29, No. 3, 365-374 (March 
1969). 

Coleman, J. A., Love, D. P., Trainor, J. H., Williams, D. J., Effects of damage 
by 0.8 MeV-5.0 MeV protons in silicon surface — barrier detectors, NASA 
Rept. No. x-611-68-221, 39 pages (National Aeronautics and Space Adminis- 
tration, Goddard Space Flight Center, Greenbelt, Md., June 1968). 

Colwell, J. H., Mangum, B. W., Utton, D. B., The low temperature magnetic 
properties of some hexagonal rare-earth trihalides, Phys. Rev. 181, No. 2, 
842-854 (May 10, 1969). 

Cook, A. R., Matarrese, L. M., Zero-field EPR of Fe 3+ in quartz, J. Chem. Phys. 
50, No. 6, 2361-2364 (March 15, 1969). 

Cooper, M. J., Green, M. S., Generalized scaling and the critical eigenvector in 
ideal Bose condensation, Phys. Rev. 176, No. 1, 302-309 (Dec. 5, 1968). 

Cooper, M. J., Point transformation of classical hard-core potential, J. Math. 
Phys. 9, No. 4, 571-578 (April 1968). 

Coriell, S. R., Hardy, S. C, Morphology of unstable ice cylinders, J. Appl. Phys. 
40, No. 4, 1652-1655 (March 1969). 

Coriell, S. R., Jackson, J. L., Bounds on transport coefficients of two-phase ma- 
terials, J. Appl. Phys. 39, No. 10, 4733-^736 (September 1968). 

Corliss, C. H., Relative oscillator strengths for lines of Tb i, J. Quant. Spectry. 
Radiative Transfer 8, 1185-1191 (1968). 

Corruccini, R. J., Principles of thermometry (measurement of temperature). 
Book, Treatise on Analytical Chemistry, I. M. Kolthoff, P. J. Ehring, and 
E. B. Sandell, Eds., Part I, Theory and Practice 8, Chapter 87, 4937-4990 
(Interscience Publ. Inc., New York, N.Y. 1968). 

Coxon, B., Studies of 15 N-labeled amino sugars. Synthesis and spectroscopy of 
derivatives of 6-amino-6-deoxy-D-glucose-6- 15 N, Carbohydrates Res. 11, 153-155 
(1969). 

CoxOn, B., P.M.R. evidence for the conformations of 1,2-0-benzylidene-a-D-gluco- 
furanose derivatives, Carbohydrate, Res. 8, 125-134 (1968). 

Crawford, B. H., Nimeroff, I., Radiation sources and their power supplies, 
Chapter in Techniques of Photostimulation in Biology, pp 19-48 (North- 
Holland Publ. Co., Amsterdam, the Netherlands, 1968). 

Crawford, M. L., A new RF-DC substitution calorimeter with automatically 
controlled reference power, IEEE Trans. Instr. Meas. IM-17, No. 4, 378-384 
(December 1968). 

Creitz, E. C, Construction details and measurements of responses of a gas 
density balance, J. Chromatog, Scie. 7, 137-144 (March 1969). 

214 



Crissman, J. M., Mechanical relaxation in polypropylene as a function of poly- 
morphism and degree of lamellar or orientation, J. Poly, Sci. 7, Part A2, 
389-404 (1969). 

Crumlish, J. D., Notes on U.S. Government information systems, Law Computer 
Technol. 1, No. 11, 15-21 (November 1968). 

Cushen, W. E., Systems analysis activities at the Technical Analysis Division 
of the National Bureau of Standards, C-E Newsletter 4, No. 3, 4-5 (June 
1969). 

Cuthill, J. R., Dobbyn, R. C, McAlister, A. J., Williams, M. L., Search for plas- 
maron structure in the soft x-ray L 2 , a emission spectrum of Al, Pyhs. Rev. 
174, No. 2, 515-517 (Oct. 10, 1968). 

Cuthill, J R., McAlister, A. J., Williams, M. L., Dobbyn, R. C, Soft x-ray spectra 
and comparison with the theoretical density of states (Proc. Conf. Soft X-ray 
Band Spectra and the Electronic Structure of Metals and Materials, Strath- 
clyde, Scotland, Sept. 18-21, 1967) Chapter in Soft X-ray Band Spectra and 
the Electronic Structure of Metals and Materials. Part II. Heavy Metal and 
Alloy Spectra and Comparison with other Optical Methods, pp. 151-162 
(Academic Press Inc., New York, N.Y. 1968) . 

Cutkosky, R. D., A varactor null detector for audio frequency capacitance 
bridges, IEEE Trans. Instr. Meas. IM-17, No. 4, 232-238 (December 1968). 

Czyz, W., Maximon, L. C, High energy scattering of strongly interacting com- 
posite particles, Physics Letters 27B, No. 6, 354-357 (August 19, 1968). 

Czyz, W., Maximon, L. C, High energy, small angle elastic scattering of strongly 
interacting composite particles, Ann. Phys. 52, No. 1, 59-121 (March 1969). 

Daniel, A. C, Bevan, A. W., Jr., Mahler, R. J., Nuclear spin-lattice relaxation 
in the antiferromagnets CoCl2-2H 2 and FeCl 2 -2H 2 0, J. Appl. Phys. 39, No. 2, 
Part I, 496-497 (Feb. 1, 1968). 

Danielson, B. L., An optical Faraday rotation technique for the determination of 
magnetic relaxation times, IEEE Trans. Mag. MAG-4, No. 2, 176-178 (June 
1968). 

Davis, D. D., Braun, W. Intense vacuum ultraviolet atomic line sources. Appl. 
Opt. 7, No. 10, 2071-2074 (October 1968) . 

Davis, D. D., Okabe, H., Determination of bond dissociation energies in hydrogen 
cyanide. Cyanogen and cyanogen halides by the photodissociation method, 
J. Chem. Phys. 49, No. 12, 5526-5531 (Dec. 15, 1968). 

Davis, G. T., Eby, R. K., Martin, G. M., Variations of the unit-cell dimensions 
of polyethylene : effect of crystalization conditions, annealing, and deforma- 
tion, J Appl. Phys. 39, No. 11, 4973-4981 (October 1968). 

Dean, J. W., Richards, R. J., Hydrostatic pressure effects in carbon and ger- 
manium thermometers (Proc. 1967 Cryogenic Engineering Conf., Stanford 
University, Stanford, Calif., Aug. 21-23, 1967), Chapter in Advances in Cryo- 
genic Engineering 13, 505-508 (Plenum Press Inc., New York, N.Y., 1968). 

Dehl, R. E., Hoeve, C. A. J., Broadline NMR study of H 2 and D 2 in collagen 
fibers, J. Chem. Phys. 50, No. 8, 3245-3251 (1969). 

DeLancey, G B., Analysis of multicomponent diaphragm cell data, J Phys 
Chem. 73, No. 5, 1591-1593 (May 1969). 

Delaplane, R. G., Ibers, J. A., Ferraro, J. R., Rush, J. J., Diffraction and spectro- 
scopic studies of the cobaltic acid system HCo0 2 -DCo0 2 , J. Chem. Phys 50, 
No. 5, 1920-1927 (Mar. 1, 1969). 

deRis, J. N., Spread of a laminar diffusion flame, Proc. Conf. Twelfth Symp. 
(International) on Combustion, Poitiers, France, July 17, 1968, pp. 241-252 
(Combustion Institute, Pittsburgh, Pa., 1969). 

Deslattes, R. D., Paretzkin, B., A small set of reference crystals for double- 
crystal topography, J. Appl. Cryst. 1, Part 3, 176-178 (September 1968). 

Deslattes, R. D., Estimates of x-ray attenuation coefficients for the elements 
and their compounds, Acta Cryst. A25, Part 1, 89-93 (January 1969). 

deWit, R., Differential geometry of the nonlinear continuum theory of dislocation 
(Proc. IUTAM Conf. Stuttgart, Germany, Aug. 28-Sept. 2, 1967), Chapter in 
Mechanics of Generalized Continua, pp. 251-261 ( Springer- Verlag, Berlin 
Germany, 1968). 

Dibeler, V. H., Liston, S. K., Mass spectrometry study of photoionization. XII. 
Boron trifluoride and diboron tetra fluoride, Inorg. Chem. 7, No. 9, 1742-1746 
(September 1968). 

Dibler, V. H., Liston, S. K., Mass spectrometry study of photoionization. IX. 
Hydrogen cyanide and acetonitrile, J. Chem. Phys. 48, No. 10, 4765-4768 (May 
15,1968). 

215 



Dibeler, V. H., Liston, S. K., Mass spectrometric study of photoionization. XI. 
Hydrogen sulfide and sulfur dioxide, J. Chem. Phys. 49, No. 2, 482^85 (July 
15,1968). 

Dibeler, V. H., Walker, J. A., Mass spectrometric study of photoionization. XIII. 
Boron trichloride and diboron tetrachloride, Inorg. Chem. 8, No. 1, 50-55 (Jan- 
uary 1969). 

Dibeler, V. H., Walker, J. A., Mass spectrometric study of photoionization. XIV. 
Nitrogen trifluoride and trifluoramine oxide, Inorg. Chem. 8, 1728-1733 (1969). 

Dick, C. E., Motz, J. W., Inelastic scattering cross sections for 200- and 400-keV 
electrons, Phys. Rev. 171, No. 1, 75-80 (July 5, 1968). 

Dickson, R. W., Spinner, S., An improved method for the determination of tor- 
sional and flexural resonance frequencies of cylindrical specimens, J. Mater. 
3, No. 3, 716-724 (1968). 

Dickson, R. W., Wachtman, J. B., Jr., Copley, S. M., Elastic constants of single 
crystal NisAl iron 10 to 850° C, J. Apl. Phys. 40, No. 5, 2276-2279 (April 
1969). 

Diller, D. E., Refractive index of gaseous and liquid hydrogen, J. Chem. Phys. 

49, No. 7, 3096-3105 (Oct. 1, 1968). 

DiMarzio, E. A., Guttman, C. M., Separation by flow, J. Polymer Sci. Polymer 
Letters 7, 267-272 (1969) . 

Dise, J. R., Significance of the test for normal consistency of hydraulic cement, 
Am. Soc. Testing Mater. Spec. Tech. Publ. 441, Cement, Comparison of Stand- 
ards and Significance of Particular Tests, pp. 3-15 (August 1968). 

Dodd, J. N., Enemark, E., Gallagher, A., Quenching of cesium resonance radiation 
by helium, J. Chem. Phys. 50, No. 11, 4838-4842 (June 1, 1969). 

Domen, S. R., Heat loss compensated calorimeter, Nature 222, No. 5198, 1061 
(June 14, 1969). 

Donovan, R. J., Husain, D., Bass, A. M., Braun, W., Davis, D. D., Kinetic spec- 
troscopic studies of Cl(3p 52 P 3 /2, 1/2) in the vacuum ultraviolet, J. Chem Phys. 

50, No. 9, 4115-1116 (May 1, 1969). 

Douglas, T. B., King, E. G., High-temperature drop calorimetry. Chapter 8 in 

Experimental Thermodynamics, J. P. McCullough and D. W. Scott, Eds., 

Vol. I, Calorimetry of Non-reacting Systems, pp. 293-331 (Butterworth and 

Co., London, England, 1968). 
Dragoo, A. L., Diffusion rates in solids, Chapter IV in Atomic Energy Review, 

O. Kubaschewski, Ed., 2, 187-202 (International Atomic Energy Agency, 

Vienna, Austria, 1968). 
Drechsel, D., Maximon, L. C, Warner, R. E., Noncoplanar p-p bremsstrahlung 

calculations at 48 and 30 MeV, Phys. Rev. 181, No. 4, 1720-1722 (May 20, 1969) . 
Drechsel, D., On the model-independent evaluation of inelastic electron scattering 

data at low momentum transfer, Nucl. Phys. A113, No. 3, 665-675 (June 7, 

1968). 
Drechsel, D., Maximon, L. C, Potential model calculation for coplanar and 

noncoplanar proton-proton bremsstrahlung, Ann. Phys. 49, No. 3, 403-444 ( Oc- 
tober 1968). 
Driver, L. D., Arthur, M. G., A wideband RF voltmeter-comparator, IEEE Trans. 

Instr. Meas. IM-17, No. 2, 146-150 (June 1968). 
Duerst, R. W., Baum, S. J., Kokoszka, G. F., Exchange coupling in two dimeric 

copper adenine complexes, Nature 222, 665-666 (May 17, 1969) . 
Dunn, G. H, Colliding beams, Proc. First Intern. Conf. Atomic Physics, New 

York, N.Y., June 3-7, 1968, Chapter in Atomic Physics, B. Bederson, V. W. 

Cohen, F. M. J. Pichanick, Eds., pp. 417-433 (Plenum Press, Inc., New York, 

N.Y.,1969). 
Dunn, G. H, Photodissociation of H 2 + and D 2 + : theory, Phys. Rev. 172, No. 1, 

172-178 (Aug. 5,1968). 
Durst, R. A., Determination of fluoride by analate additions potentiometry, 

Mikrochim. Acta, pp. 611-614 (1969) . 
Edelman, S., Roth, S., Grisham, L., Electrical generation of motion in elastomers, 

Shock and Vibration Bull. 39. Part 2, 18 pages ( Shock and Vibration Informa- 
tion Center, Naval Research Laboratory, Washington, D.C., February 1969). 
Edmiston, C, Krauss, M., Pseudonatural orbitals as a basis for the superposition 

of configurations. II. Energy surface for linear H s , J. Chem. Phys. 49, No. 1, 

192-205 (July 1,1968). 
Edmonds, J., Matroid partition. Chapter in Mathematics of the Decision Sciences. 

American Mathematical Society Lectures in Applied Mathematics 11, 335-345 

(American Mathematical Society, Providence, R. I., 1968). 
Ehrlich, M., Influence of irradiation rate on the production of F centers in 

LiF (TLD grade), Proc. Second Intern. Conf. Luminescence Dosimetry, Gat- 

216 



linburg, Tenn., Sept. 23-26, 1968, J. A. Auxier, K. Becker, E. M. Robinson, 
Eds., Paper No. CONF-680920 Health and Safety (TID-4500), pp. 322-326 
(Oak Ridge National Laboratory, Oak Ridge, Term., September 1968) ; J. 
Appl. Phys. 40, No. 2, 891-892 (February 1969). 
Ehrlich, M., Personal dosimetry : methods other than T.L.D., Proc. First Intern. 
Congress Radiation Protection, Rome, Italy, Sept. 5-10, 1966, Part 1, pp. 69-76 
Pergamon Press, Inc., New York, N.Y., 1968). 

Ehrlich, M., Thermoluminscence response of LiF to X- and gamma rays ; a study 
of rate and energy dependence over a wide range of exposures, Proc. First 
Intern. Congress Radiation Protection, Rome, Italy, Sept. 5-10, 1966, pp. 429- 
434 (Pergamon Press Inc., New York, N.Y., 1968). 

Ehrlich, M., Lamperti, P. J., Uniformity of high-energy electron-beam calibra- 
tions, Phys. Med. Biol. 14, No. 2, 305-314 (September 1968). 

Ehrlich, M., Placious, R. C, Thermoluminescence response of CaF 2 ; Mn in 
polytetrafluoroethylene to electrons, Health Phys. 15, 341-350 (1968). 

Eick, J. D., Hegdahl, T., Segregation in dental gold casting alloys, J. Dental 
Res. 47, No. 6, Part 2, 1118-1127 (November-December 1968) . 

Eicke, W. G., The zener diode, a working D-C voltage standard, 1968 IEEE 
Intern. Convention Digest, p. 71 (Mar. 1968). 

Eisenhart, C, Zelen, M., Elements of probability, Chapter 12 in Handbook of 
Physics, second edition, E. U. Condon and H. Odishaw, Eds., Part 1. Mathe- 
matics, pp. 1-163-1-197 (McGraw-Hill Book Co., Inc., New York, N.Y., 1967). 

Enemark, E. A., Gallagher, A., A pockels cell light modulator for wide angle 
radiation, Rev. Set Instr. 40, No. 1, 40-41 (January 1969). 

Engen, G. F., A method of calibrating coaxial noise sources in terms of a wave- 
guide standard, IEEE Trans. Microwave Theory Tech. MTT-16, No. 9, 636-639 
(September 1968). 

Engen, G. F., A method of determining the mismatch correction in microwave 
power measurements, IEEE Trans. Instr. Meas. IM-17, No. 4, 392-395 
(December 1968). 

Ensign, T. C, Chang, T. T., Low temperature optical-EPR sample probe using 
tunable coaxial coupling, Rev. Sei. Instr. 40, No. 2, 268-270 (February 1969). 

Ernst, M. H., Transport coefficients from time correlation functions, Lectures in 
Theoretical Physics IX C — Kinetic Theory, pp. 417-441 (Gordon and Breach 
Science Publ. Inc., New York, N.Y., 1967) . 

Evans, J. P., Sweger, D. M., Immersion cooler for freezing ice mantles on triple- 
point-of -water cells, Rev. Sci. Instr. 40, No. 2, 376-377 (February 1969). 

Evenson, K. M., Microwave magnetic-dipole transitions between excited elec- 
tronic states of CN, Phys. Rev. 178, No. 1, 1-4 (Feb. 5, 1969). 

Evenson, K. M., Broida, H. P., Wells, J. S., Mahler, R. J., Mizushima, M., Elec- 
tron paramagnetic resonance absorption in oxygen with the HCN laser, Phys. 
Rev. Letters 21, No. 15, 1038-1040 (Oct. 7, 1968). 

Fano, U., Introductory remarks, Proc. Intern. Conf. Radiation Research, Cortina, 
Italy, June 26, 1966, pp. 13-19 (North-Holland Publ. Co., Amsterdam, the 
Netherlands, 1967). 

Fano, XL, Cooper, J. W., Spectral distribution of atomic oscillator strengths, Rev. 
Mod. Phys. 40, No. 3, 441-507 (July 1968). 

Farrar, T. C, Johannesen, R. B., Coyle, T. D., Magnetic nonequi valence in the 
high resolution NMR spectra of diaborane, J. Chem. Phys. 49, No. 1, 281-285 
(July 1,1968) 

Fatiadi, A. J., Acylation of tetrahydroxy-p-benzoquinone, J. Chem. Eng. Data 13, 
No. 4, 591-593 (October 1968). 

Fatiadi, A. J., Bromine oxidation of inositols for preparation of inosose phenyl- 
hydrazones and phenylosazones, Carbohydrate Res. 8, 135-147 (1968). 

Fatiadi, A. J., Esters of benzenepentol (pentahydroxybenzene), J. Chem. Eng. 
Data 14, 118-119 (1969). 

Fatiadi, A. J., Evidence for a chair conformation of certain osotriazoles of 
inositols, Chem, Ind. 19, 617-619 (May 10, 1969). 

Fatiadi, A. J., Nature of a colored byproduct found in crude inosose phenylosa- 
zones, Carbohydrate Res. 9, 177-185 (1969). 

Feldman, A., Horowitz, D., Dispersion of the piezobirefringence of GaAs, J. Appl. 
Phys. 39, No. 12, 5597-5599 (November 1968). 

Feldman, A., Horowitz, D., Stress-induced dichroism at the absorption edge of 
SrTiOs, Solid State Commun. 6, 607-612 (1968). 

Florin, R. E., Sicilio, F., Wall, L. A., The paramagnetic species from titanous 
salts and hydrogen peroxide, J. Phys. Chem. 72, No. 9, 3154-3161 ( September 
1968). 

217 



Flynn, D. R., O'Hagan, M. E., Measurements of the thermal conductivity and 
electrical resistivity of platinum from 100 to 900° C, Englehard Indust. Tech. 
Bull. 8, No. 4, 117-147 (March 1968). 

Flynn, D. R., Watson, T. W., High temperature thermal conductivity of soils 
(Proc. 8th Conf. Thermal Conductivity, Purdue University, West Lafayette, 
Ind., Oct. 7-10, 1968), Chapter in Thermal Conductivity, pp. 913-939 (Plenum 
Press, Inc., New York, N.Y., April 1969). 

Flynn. D. R., Watson, T. W., Measurement of the thermal conductivity of soils 
to high temperature, Atomic Energy Report SC-CR-69-3059, 113 pages (1969). 

Folman, M., Klein, R., Second layer migration with trapping on first layer sites : 
hydrogen, nitrogen, and carbon monoxide on tungsten, Surface Sci. 11, No. 3, 
430-442 (August 1968). 

Forbes, E. J., A graphic method of economic feasibility analysis (Proc. Inst. 
Electronics and Automation in Publishing, Washington, D.C., 1965), Chapter 
13 in Automation and Electronics in Publishing, L. H. Hattery and G. P. Bush, 
Eds., 3, Part IV, 129-140 (Spartan Books, Washington, D.C., 1965). 

Foster, B. E., Blaine, R. L., A comparison of ISO and ASTM tests for cement 
strength, Am. Soc. Testing Mater. Spec. Tech. Publ. 441, 33-60 (1968). 

Fowler, H. A., Experiments in electron scattering. 1, Proc. Symp. Quantitative 
Aspects of Electron Microscopy, Walter Reed Institute of Pathology, Washing- 
ton, D.C., 1965; Lab. Investigations 14, No. 6, Part 2, 9-16 (1965). 

Fraction, G. F., Walker, J. C, Tauber, S. J., Connection tables from Wiswesser 
line notation: A partial algorithm (Proc. Wiswesser Line Notation Meeting, 
Army Chemical Information and Data Systems Program, Edgewood, Arsenal, 
Aberdeen, Md., Oct. 6-7, 1966, Spec. Publ. 400-8), AD665397, pp. 139-195 
(Clearinghouse for Federal Scientific and Technical Information, Springfield, 
Va., January 1968, $3.00). 

Franklin, A. D., NBS dedicates new laboratory, J. Am. Ceramic Soc. 45, No. 10, 
841-842 (1966). 

Frederick, N. V., A low loss sliding short of limited travel for precision coaxial 
transimsision lines, Proc. IEEE 56, No. 12, 2188 (December 1968). 

Frederick, N. V., A new high-frequency current standard IEEE Trans. Instr. 
Meas. IM-17, No. 4, 285-290 (December 1968) . 

Frederikge, H. P. R., Hosier, W. R., Casella, R. C, Piezoresistive effects in semi- 
conducting strontium titanate, Proc. Ninth Intern. Conf. Physics of Semicon- 
ductors, Moscow, U.S.S.R., July 23-29, 1968, pp. 1175-1180 (NAUKA, Lenin- 
grad. U.S.S.R., 1968). 

Freeman, D. H., Paulson, R. A., Chemical microstandards from ion exchange 
resin, Nature 218, 563 (1968). 

Frisch, R. C, Forman, R. A., Nuclear magnetic resonance of Ti in Ti-H systems, 
J. Chem. Phys. 48, No. 11, 5187-5190 (June 1, 1968). 

Gadsden, M., Airglow, Encyclopedia of Atmospheric Sciences and Astrogeology, 
R. W. Fairbridge, Ed., pp. 8-10 (Reinhold Publ. Co., New York, N.Y., 1967). 

Gadsden, M., Airglow motions, International Dictionary of Geophysics I, 50-56 
(1967). 

Gadzuk, J. W., Many-body tunneling-theory approach to field emission of electrons 
from solids, Surface Sci. 15, 466^82 (1969). 

Gadzuk, J. W., Band-structure effects in the field-induced tunneling of electrons 
from metals, Phys, Rev. 182, No. 2, 416-426 (June 10, 1969). 

Gallagher, A., Excitation transfer in nearly adiabatic thermal collisions, Phys. 
Rev. 179, No. 1, 105-110 (Mar. 5, 1969). 

Gallagher, A., Rubidium and cesium excitation transfer in nearly adiabatic 
collisions with inert gases, Phys. Rev. 172, No. 1, 88-96 (Aug. 5, 1968) . 

Gammon, W. H., What educators can expect from the Center for Computer Sci- 
ences and Technology, Proc. Gen. Conf. Midwestern States Educational In- 
formation Project, Des Moines, Iowa, June 20, 1967, P.L. 89-10, Title V, Sect. 
505, pp. 30-45 (Department of Public Instruction, State of Iowa, Des Moines, 
Iowa, 1967). 

Gardner, T. V., Jr., Dickson, G., Kumpula, J. W., Application of diffraction grat- 
ings to measurement of strain of dental materials, J. Dental Res. 47, No. 6, 
Part 2, 1104-1110 (November-December 1968). 

Garfinkel, S. B., Mann, W. B., A method for obtaining large numbers of meas- 
ured time intervals in radioactive dacav, Intern. J. Appl. Radiation Isotopes 
19, No. 9, 707-709 (September 1968). 

Gates, D. M., Keegan, H. J., Weidner, V. R., Spectral reflectance and planetary 
reconnaissance (Proc. Third Goddard Memorial Symp. Scientific Experiments- 
Manned Orbital Flights, Washington, D.C., Mar. 18-19, 1965), Chapter 4 in 

218 



Scientific Experiments for Manual Orbital Flights, pp. 71-86 (Western Pe- 
riodicals Co., North Hollywood, Calif., 1965). 

Gatterer, L. E., Clock synchronization experiments at VHF utilizing the ATS-1 
and ATS-3 transponders, Natl. Aeronaut. Space Admin. Report ATS Tech. 
Summary, 9 pages (.National Aeronautics and Space Administration, Greenbelt, 
Md., Feb. 16, 1968).' 

Gatterer, L. E., Bottone, P. W., Morgan, A. H., Worldwide clock synchronization 
using a synchronous satellite, IEEE Trans. Instr. Meas. IM-17, No. 4, 372-378 
(December 1968). 

Gautier, T. N., Zacharisen, D. H., Use of space and time correlations in short- 
term ionospheric predictions, First Ann. IEEE Commun. Convention, pp. 671- 
676 (June 1965). 

Gebbie, K. B., Thomas, R. N., Non-LTE diagnostic stellar spectroscopy. I. Con- 
ceptual and analytical background, Astrophys. J. 154, No. 1, 271-283 (October 
1968). 

Gebbie, K. B., Thomas, R. N., Non-LTE diagnostic stellar spectroscopy. II. On 
the Schuster mechanism for the production of emission lines, Astrophys. J. 
154, No. 1, 285-296 (October 1968). 

Geltman, S., Topics in atomic collision theory, 30, 247 pages (Academic Press 
Inc., New York, N.Y., 1969). 

Ginnings, D. C, Introduction, Chapter 1 in Experimental Thermodynamics. 
Vol. I. Oalorimetry of Nonreacting Systems, J. P. McCullough and D. W. Scott, 
Eds., pp. 1-13 (Butterworth and Co., London, England, 1968). 

Ginnings, D. C, West, E. D., Principles of calorimetric design, Chapter 4 in 
Experimental Thermodynamics, J. P. McCullough and D. W. Scott, Eds,, Vol. I, 
Calorimetry of Non-reacting Systems, pp. 85-131 (Butterworth and Co., Lon- 
don, England, 1968). 

Ginnings, D. C, Stimson, H. F., Oalorimetry of saturated fluids including de- 
termination of enthalpies of vaporization, Chapter II in Experimental Thermo- 
dynamics, J. P. McCullough and D. W. Scott, Eds., Vol. I, Calorimetry of 
Non-reacting Systems, pp. 395-420 (Butterworth and Co., London, England, 
1968). 

Glasgow, A. R., Jr., High-temperature valve for corrosive gases, Anal. Chem. 
38, 1104 (July 1966). 

Glasgow, A. R., Jr., Ross, G. S., Cryoscopy, Chapter 88 in Treatise on Analytical 
Chemistry, Part I, Theory and Practice, I. M. Kolthoff, P. J. Elving, E. B. 
Sandell, Eds., 8, 4991-5083 (Interscience Publ., New York, N.Y., 1968). 

Goldman, D. T., Reactor physicists emphasize need for neutron data, Phys. Today 
21, No. 8, 85 -89 (Aug. 21, 1968). 

Golub, S., Steiner, B., Photodetachment of [OH(H 2 Or, J. Chem. Phys. 49, No. 
11, 5191-5192 (Dec. 1, 1968). 

Gould, H. A., Guernsey, R. L., Williams, R. H., Comment on the "kinetic equation 
of a dilute gas with repulsive and attractive interactions", J. Chem. Phys. 
Letter 47, No. 2, 872-873 (July 15, 1967). 

Grabner, L., Photoluminescence in SrTi0 3 , Phys. Rev. 177, No. 3, 1315-1323 
(Jan. 15, 1969). 

Green, M. S., Generalized Ornstein-Zernike approach to critical phenomena, J. 
Math. Phys. 9, No. 6, 875-890 ( June 1968 ) . 

Greenberg, L., Kleinian groups, Proc. Am. Math. Soc. 17, No. 5, 1195-1198 (Oc- 
tober 1966). 

Grenley, D. G., Cattaneo, L. E., Pfrang, E. O., Effect of edge load on flexural 
strength of clay masonry systems utilizing improved mortars (Proc. Intern. 
Oonf. Masonry Structural Systems, University of Texas, Austin, Tex., Nov. 
30-Dec. 2, 1967), Chapter in Desinging Engineering and Constructing with 
Masonry Products, F. B. Johnson, Ed., Paper 17, pp. 119-128 (Gulf Publ. Co., 
Houston, Texas, May 1969). 

Grenley, D. G., Study of the effect of certain modified mortars on compressive 
and flexural strength of masonry (Proc. Intern. Conf. Masonry Structural 
Systems, University of Texas, Austin, Tex., Nov. 30-Dec. 2, 1967), Chapter in 
Designing Engineering and Constructing with Masonry Products, F. B. John- 
son, Ed., Paper 5, pp. 28-33 (Gulf Publ. Co., Houston, Tex., May 1969). 

Gross, D., Loftus, J. J., Lee, T. G., Gray, V. E., Smoke and gases produced by 
burning aircraft interior materials, FAA NA-68-36 (DS-68-16) 50 pages (Fed- 
eral Aviation Agency, Washington, D.C., June 1968). 

Haber, S., A combination of Monte Carlo and classical methods for evaluating 
multiple integrals, Bull. Am. Math. Soc. 74, No. 4, 683-686 (July 1968). 

Haber, S., Osgood, C. F., On a theorem of Piatetsky-Shapiro and approximation 
of multiple integrals, Math. Comput. 23, No. 105, 165-168 (January 1969). 



375-572—70 15 



219 



Halford, D., Wainwright, A. E., Barnes, J. A., Flicker noise of phase in RF 
amplifiers and frequency multipliers: characterization, cause, and cure, Proc. 
22nd Annual Symp. Frequency Control, Atlantic City, New Jersey, Apr. 22-24, 
1968, pp. 340-341 (Solid State and Frequency Control Division, Electronic 
Components Laboratory, U.S. Army Electronics Command, Fort Monmouth, 
N.J., April 1968). 

Hall, J. L., The laser absolute wavelength standard problem, IEEE J. Quantum 
Elect. QE-4, No. 10, 638-641 (October 1968). 

Haller, W., Macedo, P. B., The origin of phase connectivity in microheterogeneous 
glasses, Phys. Chem. Glasses 9, No. 5, 153-155 (October 1968). 

Halldane, J. F., Visual responses of travelers in urban enviornments, (Proc. 
Symp. Man-Machine Systems, Cambridge, England, Sept. 8-12, 1969), Chapter 
in Transport Systems Vehicle Control 2, Paper No. 8, 22 pages (1969). 

Hanley, H. J. M.. Childs, G. E., Dilute gas viscosities at low temperatures, J. 
Chem. Phys. 50, No. 10, 4600-4601 (May 15, 1969). 

Hanley, H. J. M., Childs, G. E., Interim, values for the viscosity and thermal 
conductivity coefficients of fluid He 4 between 2 and 50 K, Cryogenics 9, No. 2, 
106-111 (April 1969). 

Hanley, H. J. M., Klein, M., Selection of the intermolecular potential function 
III. From the isotopic thermal diffusion factor, J. Chem. Phys. 50, No. 11, 
4765-4770 (June 1, 1969). 

Hanley, H. J. M., McOanty, It. D., Sengers, J. V., Density dependence of experi- 
mental transport coefficients of gases, J. Chem. Phys. 50, No. 2, 857-870 
(Jan. 15, 1969). 

Hanman, N. S., Superconducting ransmission lines — communication and power, 
Proc. 1968 Summer Study on Superconducting Devices and Accelerators, Brook- 
haven National Laboratory, Upton, Long Island, N.Y., June 10-July 1968, BNL- 
50155, pp. 622-627 (1968). 

Hardy, S. C, Coreill, S. R., Morphological stability and the ice-water interfacial 
free energy, J. Crystal Growth 3, No. 4, 569-573 (1968). 

Hardy, S. C, Coreill, S. R., Morphological stability of a growing cylindrical 
crystal of ice, J. Appl. Phys. 39, No. 7, 3505-3507 (June 1968). 

Harris, W. P., Roberts, D. E., New standard reference dielectric specimens at 
NBS, Proc. 1968 Annual Report Conf. Electrical Insulation and Dielectric 
Phenomena, Oct. 21-23, 1968, Buck Hill Falls, Pa., pp. 80-84 (Natl. Acad. Sci.- 
Natl. Res. Council, Washington, D.C. 1969). 

Hartman, W. J., Feasibility of communication with a satellite by means of 
tropospheric scatter, IEEE Trans. Commun. Technol. COM-14, No. 3, 251 
(June 1966). 

Hebert, R. L, Tryon, M., Wilson, W. K., Differential thermal analysis of some 
papers and carbohydrate materials, Tappi 52, No. 6, 1183-1188 (June 1969). 

Hein, R. A., Cox, J. E., Blauggher, R. D., Waterstrat, R. M., Superconducting be- 
havior of A-15 compounds, Solid State Commun. 7, 381-384 (1969). 

Heinrich, K. F. J., Common sources of error in electron probe microanalysis, 
Advan. X-ray Anal. 11, 40-55 (1968). 

Heinrich, K. F. J., Electron probe microanalysis : a review, Appl. Spectry. 22, 
No. 5, Part 1, 395-403 (September-October 1968). 

Heinrich, K. F. J., Yakowitz, H., Quantitative electron probe microanalysis : 
fluorescence correction uncertainty, Mikrochim. Acta 5, 905-916 (1968). 

Henderson, M. M., Introductory remarks and summary of discussion for 
symposium on critical reviews, J. Cheim Doc. 8, 231 and 245 (November 1968). 

Hendricks, R. C, Simoneau, R., Smith, R. V., Heat transfer with a near-critical 
fluid, Nat. Aeronaut. Space Admin. Report TNX 52612, 97 pages (National 
Aeronautics and Space Administration, Greenbelt, Maryland, June 16, 1969). 

Herber, R. H., Spijkerman, J. J., Narrow-line sources for 119 Sn Mossbauer spec- 
troscopy, J. Chem. Phys. 43, No. 11, 4057-4059 (Dec. 1, 1965). 

Herbert, R. L., Tryon, M., Wilson, W. K., Differential thermal analysis of some 
papers and carbohydrate materials, Tappi 52, No. 6, 1183-1188 (June 1969). 

Herron, J. T., Huie, R. E., Rates of reaction of atomic oxygen (0 3 P). Experi- 
mental method and results for some Ci to C 3 chloroalkanes and bromoalkanes, 
J. Phys. Chem. 75, No. 5, 1326-1335 (May 1969). 

Herron, J. T., Penzhorn, R. D., Mass spectrometric study of the reactions of 
atomic oxygen with ethylene and formaldehyde, J. Phys. Ohem. 73, No. 1, 191- 
196 (January 1969). 

Hertelendy, P., An approximate theory governing symmetric motions of elastic 
rods of rectangular or square cross section, J. Appl. Mech. Paper No. 68- 
APM-10, pp. 333-341 (June 1968). 

220 



Heydemann, P. L. M., Houck, J. 0., Self-consistent ultrasonic method for the 
determination of the equation of state of liquids at very high pressures, 
J. Appl. Phy. 40, No. 4, 1609-1613 (Mar. 15, 1969). 

Hicho, G. E., Meyerson, M. R., Geil, G. W., Effect of slack-quenched structures 
on the tensile properties of AISI 5140 steel (Proc. Intern. Conf. Strength of 
Metals and Alloys, Tokyo, Japan, Sept. 4-8, 1967), Suppl. Trans. Japan Inst. 
Metals 9, 134-142 ( 1968 ) . 

Hiza, M. J., Duncan, A. G., A simple gas recirculation pump for low flow and 
high pressure applications, Rev. Sci. Instr. 40, No. 3, 513-514 (March 1969). 

Hiza, M. J., Heck, C. K., Kidnay, A. J., Liquid-vapor and solid-vapor equilibrium 
in the system hydrogen-ethane (Proc. 1967 Cryogenic Engineering Conf., 
Stanford University, Stanford, Calif., Aug. 21-23, 1967), Chapter in Advances 
in Cryogenic Engineering 13, 343-356 (Plenum Press Inc., New York, N.Y., 
1968). 

Hiza, M. J., Heck, C. K., Kidnay, A. J., Liquid-vapor and solid-vapor equilibrium 
in the system hydrogen-ethylene, Proc. Symp. Cryogenic Advance in the Space 
Program, Tampa, Fla., May 19-22, 1968, 64, No. 88, 57-65 (American Institute 
of Chemical Engineering, New York, N.Y., 1968). 

Hobbs, A. M., Remarks on network simplification, J. Operations Res. 15, No. 3, 
548-551 (May-June 1967). 

Hoer, C. A., Smith, W. L., A 1-MHz binary inductive voltage divider with ratios 
of 2 n to 1 or 6n dB, IEEE Trans. Instr. Meas. IM-17 No. 4, 278-284 (Decem- 
ber 1968). 

Hoffman, J. D., Lauritzen, J. I., Jr., Passaglia, E., Ross, G. S., Frolen, L. J., 
Weeks, J. J., Kinetics of polymer crystallization from solution and the melt, 
Kolloid-Z. Polymere 231, Nos. 1-2, 564-592 (1969). 

Hogben, D., The distribution of the sample variance from a two-point bino- 
mial population, Am. Stat. 32, No. 5, 30 (December 1968). 

Hoover, T. B., The N-methylpropionamide-water system. Densities and dielectric 
constants at 20-40°. J. Phys. Chem. 73, No. 1, 57-61 (January 1969). 

Hubbell, J. H., Berger, M. J., Photon attenuation. Attenuation coefficients, 
energy absorption coefficients, and related quantities, Chapter 4 in Engineer- 
ing Compendium on Radiation Shielding, R. G. Jaeger, E. P. Blizard, A. B. 
Chilton, M. Grotenhuis, A. Honig, T. A. Jaeger, H. Eisenlohr, Eds., 1, 167-202 
(International Atomic Energy Agency, Vienna, Austria, 1968). 

Hudson, G. E., Allan, D. W., Barnes, J. A., Hall, R. G., Lavanceau, J. D., Winkler, 
G. M. R., A coordinate frequency and time system, Proc. 23rd Frequency Con- 
trol Symp.. Atlantic City, N.J., May 6-8, 1969, p. 249 (1969). 

Hudson, G. E., Barnes, J. A., Clock error statistics as a renewal process, Proc. 
22nd Frequency Control Annual Symp., Atlantic City, N.J., Apr. 22^-24, 1968, 
pp. 384-413 (1968). 

Hudson, R. P., The CMN temperature scale, Proc. XI Conf. Low Temperature 
Physics, St. Andrews, Scotland, Aug. 21-28, 1968, I, 501-504, Paper D1.8 
(University of St. Andrews, Scotland, 1968). 

Hudson, R. P., The delta campaign. An account of the controversy surrounding 
the temperature scale for CMN, Cryogenics 9, No. 2, 76-79 (April 1969). 

Hudson, R. P., Kaeser, R. S., Magnetic temperature scale 0.002-5°K, Proc. Xth 
Intern. Conf. Low Temperature Physics, Moscow, U.S.S.R., Aug. 31-Sept. 6, 
1966, Vol. 1, Properties of Helium, Paper H4, pp. 171-173 (1968). 

Huget, E. F., Brauer, G. M., Reactivity of the components of tooth structure, 
J. Colloid Interface Sci. 27, No. 4, 714-721 (August 1968). 

Hummer, D. G., Non-coherent scattering-IV. Doppler redistribution functions in 
moving atmospheres, Monthly Notices Roy. Astron. Soc. 141, 479-488 
(December 1968). 

Hummer, D. G., Radiative transfer processes in planetary nebulae (Proc. Intern. 
Astronomical Union, Symp. No. 34, Tatranska Lomnica, Czechoslovakia, Sept. 
4-8, 1967), Chapter in Planetary Nebulae, D. E. Osterbrock and C. R. O'Dell, 
Eds., pp. 166-184 (D. Reidel Publ. Co., Dordrecht, Amsterdam, The Nether- 
lands, 1968). 

Hummer, D. G., Rybicki, G. B., Line formation in differentially moving media 
with temperature gradients (Proc. Natl. Center for Atmospheric Research 
Conf. Resonance Lines in Astrophysics, Sept. 9-12, 1968, Boulder, Colo., pp. 
315-330 (National Center for Atmospheric Research, Boulder, Colo., Decem- 
ber 1968). 

Hummer, D. G., Rybicki, G. B., Red-shifted line profiles from differentially 
expanding atmospheres, Astrophys. J. 153, No. 2, L107-L110 (August 1968). 

Hust, J. G., Powell, R. L., Thermal conductivity of aerospace alloys at cryo- 

221 



genie temperatures (Proc. 8th Conf. Thermal Conductivity, Purdue University, 
West Lafayette, Ind., Oct. 7-10, 1968), Chapter in Thermal Conductivity, 
C. Y. Ho and R. E. Taylor, Eds., pp. 197-208 (Plenum Press Inc., New York, 
N.Y., 1969). 

Hutchinson, J. M. R., Mann, W. B., Smith, C. N., Whittaker, J. K., The half- 
lives of two excited states in 239 Np, Intern. J. Appl. Radiation Isotopes 20, 
No. 7, 493-498 (July 1969). 

Hyde, K. E., Gordon, G., Kokoszka, G. F., Magnetic properties of some binu- 
clear copper (II) complexes, J. Inorg. Nucl. Chem. 30, 2155-2161 (1968). 

Isbell, H. S., Frush. H. L., Wade, C. W. R., Hunter, C. E., Transformations of 
sugars in alkaline solutions, Carbohydrate Res. 9, 163-175 (1969). 

Ito, J., Silicate apatites and oxyapatites, Am. Mineralogist 53, 890-907 (May- 
June 1968). 

I to, J., Johnson, H., Synthesis and study of yttrialite, Am. Mineralogist 53, 
1940-1952 (November 1968). 

Iverson, W. P., Mechanisms of microbial corrosion (Proc. First Intern. Bio- 
deterioration Symp., Southampton, England, Sept. 9-14, 1968), Chapter in Bio- 
deterioration of Materials. Microbiological and Allied Aspects, pp. 28-43 
( Elsevier Publ. Co., Ltd., Essex, England, 1968 ) . 

Iverson, W. P., Microbiological corrosion, Proc. Conf. Corrosion and Protection 
of Pipes and Pipelines, London, England, June 13, 1968, 6 pages (Technical 
Exhibited Ltd., London, England, 1968). 

Ives, J. M., Hughes, E. E., Taylor, J. K., Absolute determination of low con- 
centrations of oxygen in inert gases by means of galvanic cells, Anal. Chem. 
40, No. 12, 1853-1856 (October 1968). 

Jackson, J. L., Coriell, S. R., Transport coefficients of composite materials, J. 
Appl. Phys. 39, No. 5, 2349-2354 (April 1968) . 

Jackson, J. L., Lifson, S., Corell, S. R., Association times of counterions to 
poly electrolytes in solution, J. Chem. Phys. 50, No. 11, 5045 (June 1, 1969). 

Jacox, M. E., Milligan, D. E., Matrix-isolation study of the vacuum-ultraviolet 
photolysis of methyl fluoride. The infrared spectra of the free radicals CF, 
HCF, and H 2 CF, J. Chem. Phys. 50, No. 8, 3252-3262 (Apr. 15, 1969). 

Jacox, M. E., Milligan, D. E., Matrix-isolation study of the infrared spectrum 
of the free radical F 2 CN, J. Chem. Phys. 48, No. 9, 4040-4046 (May 1, 1968). 

Jacox, M. E., Milligan, D. E., Matrix-isolation study of the vacuum-ultraviolet 
photolysis of trichlorosilane. The infrared spectrum of the free radical SiOls, 
J. Chem. Phys, 49, No. 7, 3130-3135 (Oct. 1, 1968). 

Jespersen, J. L., Kamas, G., Gatterer, L. E., MacDoran, P. F., Satellite VHF 
transponder time synchronization, Proc. IEEE 56, No. 7, 1202-1206 (July 
1968). 

Johannesen, R. B., Candela, G. A., Tsang, T., Jahn-Teller distortion : magnetic 
studies of vanadium tetrachloride, J. Chem. Phys, 48, No. 12, 5544-5549 
(June 15, 1968). 

Johannesen, R. B., Gordon, C. L., Titanium (IV) bromide (titanium tetra- 
bromide), Chapter IV in Inorganic Syntheses IX, 46-50 (McGraw-Hill Book 
Co. Inc., New York, N.Y., 1967). 

Johnson, V. J., A memoir of Russell B. Scott (Proc. CRYO/68 Conf., Chicago, 
Illinois, June 9-12, 1968), Chapter in Applications of Cryogenic Technology, 
R. W. Vance and H Weinstock, ed., Introduction, pp. 1-11 (Tinnon-Brown, 
Inc., Los Angeles, Calif., 1969). 

Johnson, V. J., Development and operation of a specialized technical information 
and data center (The Cryogenic Data Center), J. Chem. Doc. 8, No. 4, 219-224 
(November 1968). 

Joiner, B. L., Rosenblatt, J. R., The mean deviation and range for n=3, Am. 
Stat. 22, No. 4, 37-38 (October 1968). 

Jones, E., Yelon, W. B., Edelman, S., Piezoelectric shakers for wide-frequency 
calibration of vibration pickups, J. Acoust. Soc. Am. 45, No. 6, 1556-1559 (June 
1969). 

Jones, M. C, Giarratano, P. H., Simpson, A. U., Flow and heat transfer charac- 
teristics of sub-triple-point cryogens in heated tubes, Proc. Second Intern. 
Cryogenic Engineering Conf., Brighton, England, May 7-10, 1968, pp. 83-88 
(Iliffe Science and Technology Publ., Ltd., Guilford, Surrey, England, 1968). 

Jones, M. C, Palmer, D. C, A technique for the measurement of spectral re- 
flectances at low temperatures in the infrared and far infared (Proc. AIAA 
Third Thermophysics Conf., Los Angeles, Calif., June 24-26, 1968), Chapter in 
Progress in Astronautics and Aeronautics. Vol. 21, Thermal Design Principles 

222 



of Spacecraft and Entry Bodies, pp. 543-557 (Academic Press Inc., New York, 
N.Y., 1969). 

Judd, D. B., 1964 CIE supplementary observer applied to the colorimetry of 
rutile and anatase forms of titanium dioxide, J. Opt. Soc. Am. 58, No. 12, 
1638-1649 (December 1968). 

Judd, D. B., Oolor science and the paint industry, J. Paint Technol. 40, No. 525, 
470-477 (October 1968). 

Kahn, A. H., Polarons in anisotropic energy bands, Phys. Rev. 172, No. 3, 813- 
815 (Aug. 15, 1968). 

Kamper, R. A., Cryoelectronics, Cryogenics 9, No. 1, 20-25 (February 1969). 

Kamper, R. A., Possible contribution of superconducting devices to nuclear mag- 
netic resonance detection, J. Appl. Phys. 40, No. 5, 2163 (April 1969). 

Kaufman, V., Radziemski, L. J., Redetermined level values and interaction param- 
eters of S i and CI n ground configurations, J. Opt. Soc. Am. 59, No. 2, 227- 
228 (February 1969). 

Keller, R. A., Excited triplet-^ singlet intersystem crossing, Cheni. Phys. Letters 
3, No. 1, 27-29 (January 1969). 

Keller, R. A., Intersystem crossing from excited triplet states into the singlet 
manifold (Proc. Intern. Conf. Molecular Luminescence, Loyola Univ., Chicago, 
111., Aug. 20-23, 1968), Chapter in Molecular Luminescence, E. C. Lim, Ed., pp. 
453-468 (W. A. Benjamin Inc., New York, N.Y., 1969). 

Keller, R. A., Dolby, L. J., Intramolecular energy transfer between triplet states 
of weakly interacting chromophores. III. Compounds in which the chromophores 
are separated by a rigid steroid bridge, J. Am. Chem. Soc. 91, No. 6, 1293-1299 
(September 1969). 

Kelley, R. D., Klein, R., Scheer, M. D., The cis-trans effect in the H-atom addi- 
tion to olefins, J. Phys. Chem. 73, No. 4, 1169-1170 (April 1969). 

Kidnay, A. J., Hiza, M. J., Dickson, P. F., The adsorption isotherms of methane, 
nitrogen, hydrogen and their mixtures on charcoal at 76° K (Proc. 1967 
Cryogenic Engineering Conf., Stanford University, Stanford, Calif., Aug. 21-23, 
1967), Chapter in Advances in Cryogenic Engineering 13, 397-408 (Plenum 
Press Inc., New York, N.Y., 1968). 

Kim, Y-K, Inokuti, M., Chamberlain, G. E., Mielczarek, S. R., Minima of gen- 
eralized oscillator strengths, Phys. Rev. Letters 21, No. 16, 1146-1148 (Oct. 14, 
1968). 

King, R. J., Maley, S. W., Wait, J. R., Experimental and theoretical studies of 
propagation of ground waves across mixed paths (Proc. URSI Symp. Electro- 
magnetic Wave Theory, Delft, Holland, September 1965), Chapter in Electro- 
magnetic Wave Theory, J. Brown, Ed., pp. 217-224 (Pergamon Press Inc., 
New York, N.Y., 1965). 

Kirby, R. K, Rothrock, B. D., Thermal expansion of vitreous selenium from 
— 190° to +30° C, J. Am. Ceram, Soc. 51, No. 9, 535 (September 1968). 

Kirchhoff, W. H., The microwave spectrum, structure, and dipole moment of 
cis-thionylimide, J. Am. Chem. Soc. 91, 2437-2442 (1969). 

Klein, M., Hanley, H. J. M., Selection of the intermolecular potential. Part 2. 
From data of state and transport properties taken in pairs, Trans. Faraday 
Soc. 64, Part II, No. 551, 2927-2938 (November 1968). 

Klein, R., The deposition of hydrogen beams on tungsten, Surface Sci. 11, No. 2, 
227-241 (July 1968). 

Klein, R., Scheer, M. D., Reaction of 0( 3 P) with 2-methyl-2-pentene at low 
temperatures and its implication for the transition state, J. Phys. Chem. 73, 
1598-1599 (1969). 

Klemens, P. G., Jackson, J. L., Diffusion of electrons on the Fermi surface. II. 
Longitudinal magnetoresistance of lb metals, Physica 31, 1421-1427 (1965). 

Klose, J. Z., Atomic lifetime measurements with pulsed electron beams, (Proc. 
Beam-Foil Spectroscopy Conf., Univ. of Arizona, Tucson, Ariz., Nov. 20-22), 
Chapter in Beam-Foil Spectroscopy II, 285-304 (Gordon and Breach Science 
Publ. Inc., New York, N.Y., 1968). 

Klose, J. Z., Experimental lifetimes of the 5p levels in argon I, J. Opt. Soc. Am. 
58, No. 11, 1509-1512 (November 1968). 

Klose, J. Z., Transition probabilities and mean lives of the 2S* laser level in 
neon I, J. Quant. Spec. Rad. Trans. 9, No. 6. 881-883 (June 1969). 

Koidan, W., Calibration of standard condenser microphones : coupler versus 
electrostatic actuator, J. Acoust. Soc. Am. 44, No. 5, 1451-1453 (November 
1968). 

Kokoszka, G. F., Allen, H. C, Jr., Gordon, G., Electron paramagnetic resonance 
spectra of two zinc-doped and nickel-doped copper chloride pyridine-2V-oxide 
complexes, J. Chem. Phys. 46, No. 8, 3020-3024 (Apr. 15, 1967). 

223 

375-572—70 16 



Kokoszka, G. F., Linzer, M., Gordon, G., Electron paramagnetic resonance spec- 
tra of polycrystalline dimeric complexes. Copper propionate monohydrate and 
zinc-doped copper propionate monohydrate, Inorg. Chem. 7, No. 9, 1730-1735 
(September 1968). 

Koonce, C. S., Tunneling into low carrier density superconductors, Phys. Rev. 
182, No. 2, 5407 (June 10, 1969). 

Koonce, C. S., Cohen, M. L., Theory of superconducting semiconductors and 
semimentals, Phys. Rev. 177, No. 2, 707-719 (Jan. 10, 1969). 

Kopec, C. S., Measurement of gears, Chapter 15 in Handbook of Industrial 
Metrology, pp. 424-450 (Prentice-Hall, Inc., Englewood Cliffs, N.J., 1967). 

Kraft, R., An unusual mixed initial boundary problem in two independent vari- 
ables, J. Math. Anal. Appl. 25, No. 2, 233-249 (February 1969). 

Krause, R. F., Jr., Douglas, T. B., The heats of formation of A1C1F 2 and 
A1C1 2 F from subliming A1F 3 in the presence of A1C1 3 vapor, J. Phys. Chem. 
72, No. 10, 3444-3451 (October 1968) . 

Kropschot, R. H., Report on the fourteenth cryogenic engineering conference, 
Cryogenics 8, No. 6, 346-348 (December 1968) . 

Kruger, J., The spectrum of corrosion research of the Corrosion Section of the 
National Bureau of Standards (Proc. 12th Annual Appalachian Underground 
Corrosion Short Course, West Virginia University, Morgantown, W. Va., Oct. 
1967), West Virginia University Tech. Bull. 86, 11-13, (1967). 

Ku, H. H., Expressions of imprecision, systematic error, and uncertainty asso- 
ciated with a reported value, Meas. Data 2, No. 4, 72-77 (July- August 1968). 

Kuehner, E. C, Freeman, D. H., Containers for pure substances, Chapter in 
Purification of Inorganic and Organic Materials, M. Yief, Ed., pp. 297-306 
(Marcel Dekker, Inc., New York, N.Y., 1969) . 

Kuriyama, M., Theory of x-ray diffraction by a distorted crystal. II. Scattering 
amplitude for a wave packet of finite size, J. Phys. Soc. Japan 25, No. 3, 846- 
856 (September 1968). 

Kushner, L. M., The National Bureau of Standards and the Fire Research and 
Safety Act of 1968, Fire J. 62, No. 5, 32-33, 118 (September 1968). 

Kusuda, T., Thermal response factors for multi-layer structures of various heat 
condition systems, ASHRAE Trans. 75, No. 1, V.3.1-V.3.25 (1969). 

Kusuda, T., Proposed procedures for determining building heating and cooling 
loads for energy calculations, ASHRAE Symposium Bulletin, pp. 1-75 ( 1969 ) . 

Kuyatt, C. E., Measurement of electron scattering from a static gas target, 
Chapter 1 in Methods of Experimental Physics. Vol. 7. Atomic and Electron 
Physics, Electron-Atom Interactions, B. Pederson and W. L. Fite, Eds., pp. 
1^3 (Academic Press Inc., New York, N.Y., 1968). 

Lafferty, W. J., Maki, A. G., Pringle, W. C, Jr., Comments on "two rotational 
lines of allene C 3 H 4 ", J. Chem. Phys. 50, No. 1, 564-565 (Jan. 1, 1969). 

Lance, H. W., Metrology and national goals (Proc. 22nd ISA Conf. and Exhibit, 
Chicago, HI., Sept. 11-14, 1967), ISA Preprint No. M4-1-MESTIND-67, 1-14 
(1967) ; excerpt in Meas. Data 2, No. 2, 68-71 (March- April 1968). 

Lang, S. B., Shaw, S. A., Rice, L. H., Timmerhause, K. D., Pyroelectric thermom- 
eter for use at low temperatures, Rev. Sci. Instr. 40, No. 2, 274-284 (Feb- 
ruary 1969). 

Lashof, T. W., Standardization and application of accuracy and precision state- 
ments : TAPPI Standards Committee-ASTM Committee D-6 policy, Tappi 4, 
732-739 (April 1969). 

Latanision, R. M., Staehle, R. W., Plastic deformation of electrochemically 
polarized nickel single crystals, Acta Met. 17, 307-319 (March 1969). 

Laufer, A. H., Photolysis of ketene. Mechanism of hydrogen production and the 
reaction of methylene with methane, J. Phys. Chem. 73, No. 4, 959-963 (April 
1969). 

Laufer, A. H., McNesby, J. R., Photolysis of methane at 1236-A : quantum yield 
of hydrogen formation, J. Chem. Phys. 49, No. 5, 2272-2278 (Sept. 1, 1968). 

Lederer, P. S., Pressure, ISA Transducer Compendium, Second edition, Chapt. 1, 
Parti, pp. 5-8 (1969). 

Lee, T. G., A system for continuously monitoring hydrogen chloride concentra- 
tions in gaseous mixtures using a chloride ion-selective electrode, Anal. Chem. 
41, 391-392 (February 1969). 

Lehner, J., Newman, M., On Reimann surfaces with maximal automorphism 
groups, Glasgow Math. J. 8, Part 2, 102-112 (July 1967). 

Leiss, J. E., Electron linear accelerators as sources of high intensity neutron 
bursts, Proc. Seminar on Intense Neutron Sources, Santa Fe, N. Mex., Sept. 
19-23, 1966, Report No. CONF-660925, pp. 605-616 (1966). 

224 



Leiss, J. E., Penner, S., Rose, J. E., Broberg, J. B., Transient beam loading in 
electron linear accelerators (Proc. 1969 Particle Accelerator Conf., Washing- 
ton, D.O., Mar. 5-7, 1969), IEEE Trans. Nucl. Sci. NS-16, Part I, No. 3, 1027- 
1030 (June 1969). 

Leiss, J. E., The NBS linac, Proc. Linear Accelerator Conf., Los Alamos, N. Mex., 
Oct 3-7, 1966, Report No. LA-3609, p. 20 (1966) . 

Leslie, R. T., Kuehner, E. C, Ebulliometry, Chapter 89 in Treatise on Analytical 
Chemistry, 8, Part D-5, 5085-5109 (1968). 

Levin, E. M., X-ray determination of the thermal expansion of silver nitrate, 
J. Am. Ceramic Soc. 52, No. 1, 53-54 (January 1969). 

Levin, I. W., Abromowitz, S., Vibrational spectra and force field for ruthenium 
tetroxide, J. Chem. Phys. 50, No. 11, 4860 (June 1, 1969). 

Lide, D. R., Jr., Structure of the alkali hydroxides, IV. Interpretation of vibra- 
tion-rotation interactions in CsOH and RbOH and refinement of structures, 
J. Chem. Phys. 50, No. 7, 3080-3086 (Apr. 1, 1969). 

Linzer, M., Line parameters of Lorentzian curves containing arbitratary mixtures 
of absorption and dispersion, J. Appl. Phys. 40, No. 1, 372-376 (January 1969). 

Lipkin, H. J., Meshkov, S., The importance of the rjir decay mode in the split A 2 
decay, Phys. Rev. Letters 22, No. 5, 212-213 (Feb. 3, 1969). 

Lippincott, E. R., Stromberg, R. R., Grant, W. H., Cessac, G. L., Poly water, Sci- 
ence 164, 1482-1487 (June 27, 1969). 

Little, W. E., Patty, O. L., Zanboorie, M. H., A millimeter wave reflectometer, 
IEEE Trans. Microwave Theory Tech. MTT-16, No. 2, 121 (February 1968). 

Litovitz, I., Macedo, P. B., Ultrasonic relaxation, viscosity, and free volume in 
molten glasses (Proc. Intern. Conf. Physics of Non-crystalline Solids, Delft, 
The Netherlands, July 6-10, 1964), Book, Physics of Non-crystalline Solids, 
J. A. Prens, Ed., p. 220 (North Holland Publ. Co., Amsterdam, the Netherlands, 
1965). 

Lloyd, E. C, Erasable trance recording methods for chart recorders, Rev. Sci. 
Instr. 39, No. 12, 1953-1954 (December 1968). 

Lloyd, E. C, Standards for improved measurement of pressure and vacuum 
(Proc. 4th Intern. Measurement Conf., Warsaw, Poland, July 2-7, 1967), Acta 
Imeko pp. 451-468 (Hungarian Academy of Sciences, Budapest, Hungary, 
1967). 

Lloyd, E. C, Beckett, C. W., Boyd, F. R, Jr., Measurements in the high-pressure 
environment, Science 164, 860-861 (May 16, 1969). 

Logan, H. L., Studies of hot salt cracking of the titanium 8%-Al-l% Mo=l% 
V alloy (Proc. Ohio State Stress Corrosion Symp., Ohio State University, 
Columbus, Ohio, Sept. 11-15, 1967), pp. 662-672 (National Association of 
Corrosion Engineers, Houston, Tex., 1969). 

Lonie, M., A report on body sizing for boys and students, Boys' and Young Men's 
Apparel Buyers' Assoc. J. p. 8 (1967) . 

Lutz, G. J., Calculation of sensitivities in photon activiation analysis, Anal. 
Chem. 41, No. 3, 424-427 (March 1969). 

Lutz, G. J., DeSoete, D. A., Determination of carbon in sodium, by photon activa- 
tion analysis, Anal. Chem. 40, No. 4, 820-822 (April 1968). 

McOaa, W. D., Jr., Nahman, N. S., Frequency and time domain analysis of a 
superconductive coaxial line using the BOS theory, J. Appl. Phys. 40, No. 5, 
2098-2100 (April 1969). 

McCaa, W. D., Jr., Nahman, N. S., Phenomena and devices, frequency and time- 
domain analysis of a superconductive coaxial line using the two-fluid model, 
J. Appl. Phys. 39, No. 6, 2592-2596 (May 1968) . 

McCamy, C. S., A half century of photographic standardization in the United 
States, Photo. Sci. Engr. 12, No. 6, 308-312 (November-December 1968). 

McCamy, C. S., Photographic image structure evaluation, Chapter in Ultra- 
Microminiaturization Precision Photography for Electronic Circuitry, pp. 130- 
140 (Society for Photographic Scientists and Engineers, Washington, D.C., 
1968). 

McCamy, C. S., Units for logarithmic scales, Phys. Today 22, No. 4, 42-44 (April 
1969). 

McClintock, M., Jennings, D. A., Mizushima, M., Contribution to the Raman line 
profile in liquids from molecular reorientation, Phys. Rev. Letters 21, No. 5, 
276-278 (July 29, 1968). 

Mclntyre, D., Mazur, J., Wims, A. M., Effects of excluded volume on light 
scattered from flexible macromolecules, J. Chem. Phys. 49, No. 7, 2887-2895 
(Oct. 1, 1968). 

Mclntyre, D., Sengers, J. V., Study of fluids by light scattering, Chapter 11 in 
Physics of Simple Liquids, H. N. V. Temperley, J. S. Rowlinson, G. S. Rush- 

225 



brooke, Eds., pp. 449-505 (North Holland Publ. Co., Amsterdam, the Nether- 
lands, 1968). 

McKinley, J. D., Jr., Mass spectrometric investigation of the surface reaction of 
tungsten with chlorine-oxygen mixtures (Proc. 6th Intern. Symp. Reactivity 
of Solids, Schenectady, N.Y., Aug. 25-30, 1968), Chapter in Reactivity of Solids, 
J. W. Mitchell. R. C. DeVries, R. W. Roberts, and P. Cannon, Eds., pp. 345-351 
(John Wiley & Sons, Inc., New York, N.Y., 1969) . 

McMurdie, H. F., Progress in X-ray diffraction data compilations, Chapter in 
Fifty Years of Progress in Metallographic Techniques, Am. Soc. Testing Mater. 
Spec. Tech. Publ. 430, 192-200 (1968). 

McNesby, J. R., The photochemistry of Jupiter above 1200 A, J. Atmospheric 
Sci. 26, No. 3, 594-599 (May 1969) . 

McNesby, J. R., Kelley, R. V., High temperature vacuum ultraviolet photolysis 
of n-butane, Jr. Phys. Chem. 73, No. 4, 789-793 (April 1969). 

Macedo, P. B., Napolitano, A., Inadequacies of viscosity theories for B 2 Os, J. 
Chem. Phys. 49, No. 4, 1887-1895 (Aug. 15, 1968). 

Macedo, P. B., Simmons, J. H., Haller, W., Spectrum of relaxation times and 
fluctuation theory : ultrasonic studies on an alkali-borosilicate melt, Phys. 
Chem. Glasses 9, No. 5, 156-164 (October 1968). 

Macek, J. H., Application of the Fock expansion to doubly excited states of the 
helium atom, Phys. Rev. 160, No. 1, 170-174 (Aug. 5, 1967). 

Madden, R. P., Ederer, D. L., Codling, K., Resonances in the photo-ionization 
continuum of An (20-150 eV), Phys, Rev. 177, No. 1, 136-151 (Jan. 5, 1969). 

Madey, T. E., Yates, J. T., Jr., Desorption by electron impact: oxygen adsorbed 
on tungsten, Surface Sci. 11, No. 2, 327-351 (July 1968). 

Madey, T. E., Yates, J. T., Jr., The measurement of sticking coefficients at high 
temperature using the isotopic mixing method (Proc. Sixth Intern. Symp. 
Rarefied Gas Dynamics, Cambridge, Mass., July 22-26, 1968), Chapter in the 
Measurement of Sticking Coefficients at High Temperatures Using the Isotopic 
Mixing Method II, 1345-1348 (Academic Press Inc., New York, N.Y. 1969). 

Maeda, K., Young, J., Propagation of the pressure waves produced by auroras, 
J. Geomagnetism Geoelectricity 18, No. 2, 275-299 (1966). 

Mahaffey, C. T., Basic construction standards and a technical information cen- 
ter recommended at a Pan American seminar, ASA Mag. Std. 36, No. 12, 
375-377 (December 1965). 

Mahler, R. J., Interaction of Gunn domains with the Ga 71 nuclei in GaAs, Appl. 
Phys. Letters 14, No. 9, 277-279 (May 1, 1969) . 

Maki, A. G., Jr., Vibrational spectroscopy, Ann. Rev. Phys. Chem. 20, 273-292 
(1969). 

Maki, A. G., Comment on the fermi resonance constant in ION, J. Chem. Phys. 
50, No. 5, 2273 (Mar. 1. 1969) . 

Mangum, B. W., Soulen, R. J., Utton, D. B., Magnetic ordering in cerium trichlor- 
ide at low temperatures, Proc, XI Conf. Low Temperature Physics, St. Andrews, 
Scotland, Aug 21-28, 1968, 2, 1361-1363, Paper C10.9 (University of St. 
Andrews. Scotland, 1968). 

Mangum, B. W., Thornton, D. D., Nuclear relaxation measurements of 35 C1 in 
PrCL Phys. Rev. Letters 22, No. 21, 1105-1107 (May 26, 1969). 

Mann, D. E., Acquista, N., Linevsky, M. J., An electronic band spectrum of yttrium 
monofluoride (Proc. 4th Rare Earth Research Conf., Phoenix, Ariz., Apr. 22- 
25, 1964), Chapter in Proceedings of the Fourth Conference on Rare-Earth 
Research, pp. 363-372 (Gordon and Breach, New York. N.Y., 1965). 

Mann. D. E., White, D., Seshadri, K. S., Dever. D. F., Linevsky, M. J., The 
infrared spectra, structures and thermodynamics of gaseous LiO, Li 2 and 
Li 2 2 , J. Chem. Phys. 39, 2463-2473 (1963). 

Manning, J. R., Vacancy-wind effect in diffusion and deviations from thermo- 
dynamic equilibrium conditions. Can. J. Phys. 46, No. 23, 2633-2643 (1968). 

Marcus. M., Newman, M., Doubly stochastic associated matrices, Duke Math. J. 
34, No. 3, 591-598 (September 1967). 

Marezio, M., Remeika, J. P., Zocchi, M., Cation distribution in the garnet 
EusFei.^Gaa.oeOis, J. Chem. Phys. 48, No. 3, 1094-1096 (February 1968). 

Margoshes, M., Remarks on linearization of characteristic curves in photo- 
graphi photometry, Appl. Opt. 8, No. 4, 818 (April 1969). 

Marinenko, G., On the atomic weight of potassium, Talanta 16, 1339-1340 
(1969). 

Marinenko, G., Taylor, J. K., Electrochemical equivalents of benzoic and oxalic 
acid, Anal. Chem. 40, No. 11, 1645-1651 (September 1968). 

226 



Martin, W. C, Tech, J. L., Wilson, M., Note on the SpHsM configuration in 
neutral potassium (Ki), Phys, Rev. 181, No. 1, 66-69 (May 5, 1969). 

Marton, L., Photoelectricity, Encyclopedia of Physics, R. M. Besancon, Ed., pp. 
512-514 (1966). 

Marzetta, L. A., Noise limitations in signal detectors, Instr. Technol. 16, No. 2, 
51-53 (February 1969). 

Mather, J. N., Invariance of the homology of a lattice, Proc. Am. Math. Soc. 17, 
No. 5, 1120-1124 (October 1966) . 

Matsumura, C, Lide, D. R., Jr., Structure of the alkali hydroxides, III. Micro- 
wave spectra of RbOH and RbOD, J. Chem Phys. 50, No. 1, 71-75 (Jan. 1, 
1969). 

Mattis, R. L., Phillips, W. E., Bullis, W. M., Measurement and interpretation 
of carrier lifetime in silicon and germanium, Tech. Rept. APML-TR-68-81, 
91 pages (Air Force Materials Laboratory, Air Force Systems Command, 
Wright- Patterson Air Force Base, Ohio, July 1968). 

Maximon, L. C, Comments on radiative corrections, Rev. Mod. Phys. 41, No. 1, 
193-204 (January 1969). 

May, L., Spijkerman, J. J., On the relationship between Mossbauer spectroscopy 
and the nuclear magnetic resonance of organotin compounds, J. Chem. Phys. 
Letter to the Editor 46, No. 8, 3272r-3273 (Apr. 15, 1967). 

Mazur, J., McCrackin, F. L., Monte Carlo studies of configurational and thermo- 
dynamic properties of self-interacting linear polymer chains, J. Chem. Phys. 
49, No. 2, 648-665 (July 15, 1968). 

Matarrese, L. M., Wells, J. S., Peterson, R. L., EPR spectrum of Fe 3+ in Synthetic 
brown quartz, J. Chem. Phys. 50, No. 6, 2350-2360 (Mar. 15, 1969). 

Mazur, J., Mclntyre, D., Wims, A. M., Asymptotic behavior of the light-scattering 
function of coiled molecules, J. Chem. Phys. 49, No. 7, 2896-2904 (Oct. 4, 1968). 

Mears, T. W., Young, D. S., Measurement and standard reference materials in 
clinical chemistry, Am. J. Clin. Pathol. 50, No. 4, 411-421 (October 1968). 

Melmed, A. J., Field emission microscopy, Chapter in Advances in Materials 
Research, Vol. I. Experimental Methods, H. Herman, Ed., pp. 103-143 (Inter- 
science Publ. Inc., New York, N.Y., 1967) . 

Melmed, A. J., Whiskers, thin films, and applications (real and imagined) to 
mass spectrometry and biological molecule imaging, Chapter in Field-Ion 
Microscopy, J. J. Hren and S. Ranganathan, Eds., pp. 183-212 (Plenum Press 
Inc., New York, N.Y., 1968) . 

Melmed, A. J., Layer, H. P., Kruger, J., Ellipsometry, low energy electron diffrac- 
tion and field emission microscopy combined, Surface Sci. 9, 476-483 (1968). 

Mendlowitz, H., Calculated line strengths for the transitions between the con- 
figurations (3(F+M 2 4s) and 3(Z"4p in Ti-n, Astrophys. J. 154, 1099-1110 
(December 1968). 

Menis, O., Rains, R. C, Determination of arsenic by atomic absorption spec- 
trometry with an electrodeless discharge lamp as a source of radiation, Anal. 
Chem. 41, No. 7, 952-954 (June 1969). 

Menke, J. L., Beam monitoring at the NBS linac-energy, positioning, current, 
charge (Proc. 1969 Particle Accelerator Conf., Washington, D.C., March 5-7, 
1969), IEEE Trans. Nucl. Sci. NS-16, Part I, No. 3, 1027-1030 (June 1969). 

Meshkov, S., Ponzini, R., Su(6)w and high-energy photoproduction, Phys. Rev. 
175, No. 5, 2030-2034 (Nov. 25, 1968). 

Meyerson, M. R., Giles, P. M., Newfeld, P. F., Dimensional stability of gage 
block materials, J. Mater. 3, No. 4, 727-743 (1968). 

Melmed, A. J., Single-specimen FEM-LEED studies: carbon on tungsten, J. 
Appl. Phys. 40, No. 5, 2330-2334 (April 1969). 

Melmed, A. J., Surface characterization by ellipsometry low-energy electron 
diffraction, and field-electron microscopy (Proc. Conf. Third Battelle Memorial 
Institute Materials Science Colloquium, Kronberg, Germany, May 6-11, 1968), 
Chapter in Molecular Processes on Solid Surfaces, pp. 105-127 (McGraw- 
Hill Book Co., Inc., New York, N.Y., 1969). 

Mielenz, K. D., Gas lasers and conventional sources in interferometry, Chapter 
in Electron Beam and Laser Beam Technology, pp. 89-137 (Academic Press 
Inc., New York, N.Y., 1968). 

Mielenz, K. D., Length measurement and laser wavelength stability, ISA Trans. 
6, No. 4, 293-297 (1967). 

Mies, F. H, Configuration interaction theory. Effects of overlapping resonances, 
Phys. Rev. 175, No. 1, 164-175 (Nov. 5, 1968). 

Mighell, A. D., Reimann, C. W., Mauer,F. A., The cyrstal and molecular structure 
of diaquobis-(2,2'-biimidazole) nickel(II) dinitrate, Ni(C 6 H 6 N 4 )"(H,0)2(N03),, 
Acta. Cryst. B25, Part 1, 60-66 (January 1969). 

227 



Migiiell, A. D., Reimann, C. W., Mauer, F. A., The crystal and molecular structure 
of dibromotetrapyrazole nickel (II), Ni(CsH 4 N 2 )4Br 2 , Acta Cryst B25, Part 3, 
595-599 (March 1969). 

Mighell, A. D., Smith, J. P., Brown, W. E., The crystal structure of phosphoric 
acid hemihydrate, H 3 P04-1/ 2 H 2 0, Acta. Cryst. 25, 776 (1969). 

Miller, O. E., Lipsicas, M., Nuclear spin-lattice relaxation in very dilute solutions 
of orthohydrogen in parahydrogen, Phys. Rev. 176, No. 1, 273-279 (Dec. 5, 
1968) . 

Milligan, D. E., Jacox, M. E., Matrix-isolation study of the reaction of F 2 and F 
atoms with NON. The infrared spectra of the species NF 2 CN and FN ON, J. 
Chem. Phys. 48, No. 11, 4811-4816 (June 1, 1968). 

Milligan, D. E., Jacox, M. E., Matrix-isolation study of the vacuum-ultraviolet 
photolysis of dichlorosilane. The infrared spectrum of the free radical SiCl 2 , 
J. Chem. Phys. 49, No. 4, 1938-1942 (Aug. 15, 1968). 

Milligan, D. E., Jacox, M. E., Matrix-isolation study of the vacuum-ultraviolet 
photolysis of difluorosilane. The infrared and ultraviolet spectra of the free 
radical SiF 2 , J. Chem. Phys. 49, No. 10, 4269-4275 (Nov. 15, 1968). 

Milligan, D. E., Jacox, M. E., Guillory, W. A., Matrix-isolation study of the 
vacuum-ultraviolet photolysis of trifluorosilane. The infrared spectrum of the 
free radical SiF 3 , J. Chem. Phys. 49, No. 12, 5330-5335 (Dec. 15, 196S). 

Mills, R. M., Flame inhibition with electron attachment as the first step, Com- 
bustion and Flame 12, No. 2, 513-520 (December 1968). 

Moore, C. E., Annual report on spectroscopy, Bull. Am. Astron. Soc. 1, No. 1, 
85-86 (January 1969). 

Moore, G. A., Application of computers to quantitative analysis of microstructures 
(Proc. Third Intern. Materials Symp., Berkeley, Calif., June 13, 1966). Chapter 
3 in Ceramic Microstructures, R. M. Fulrath and J. A. Pask, ed., pp. 71-120 
(John Wiley & Sons, Inc., New York, N.Y., 1968). 

Moore, G. A., Automatic scanning and computer processes for the quantitative 
analysis of micrographs and equivalent subjects (Proc. Symp. Automatic 
Photo Interpretation, Washington, D.C., May 31- June 2, 1967), Chapter in 
Pictorial Pattern Recognition, G. C. Cheng, R. S. Ledley, D. K. Pollock, and 
A. Rosenfeld, Eds., pp. 275-326 (Thompson Book Co., Washington, D.C., 1968). 

Moore, G. A., Wyman, L, L., Joseph, H. M., Comments on the possibilities of per- 
forming quantitative metallographic analyses with a digital computer. Chapter 
13 in Quantitative Microscopy, pp. 380-430 (McGraw-Hill Book Co. Inc., New 
York, N.Y., 1968). 

Mopsik, F. I., Dielectric constant and loss, Digest of Literature on Dielectrics 
31, 56-79 (1969). 

Mopsik, F. I., Dielectric properties of slightly polar organic liquids as a function 
of pressure, volume, and temperature, J. Chem. Phys. 50, No. 6, 2559^2569 
(Mar. 15, 1969). 

Mopsik, F. I., The effect of pressure, volume and temperature on the dielectric 
constant of simple organic liquids, Proc. 1967 Annual Report Conf. Electrical 
Insulation and Dielectric Phenomena, Buck Hill Falls, Pa., Sept. 18-20, 1967, 
pp. 66-69 (Natl. Acad. Sci.-Natl. Res. Council, Washington, D.C., 1968). 

Mountain, R. D., Deutch, J. M., Light scattering from binary solutions, J. Chem. 
Phys. 50, No. 3, 1103-1108 (Feb. 1, 1969). 

Mozer, B., Localized modes, resonant modes and impurity vibrational bands in 
vanadium alloys, Chapter in Neutron Inelastic Scattering 1, 55-63 (Interna- 
tional Atomic Energy Agency, Vienna, Austria, 1968) . 

Mullen, L. O., Sullivan, D. B., Fabrication of tunnel junctions on niobium films, 
J. Appl. Phys. 40, No. 5, 2115-2117 (April 1969). 

Mulroy, W. J., Kusuda, T., Phillips, C. W., Survey on digital computer programs 
for heating and cooling load calculations, SICCAP Bull. 2, No. 2, 4-8 (May 
1968). 

Munis, R. H., Finkel, M. W., Goniometric measurements of infrared transmitting 
materials, Appl. Opt. 7, No. 10, 2001-2004 (October 1968). 

Nargolwalla, S. S., Przybylowicz, E. P., Suddueth, J. E., Birkhead, S. L., Solu- 
tion of blank problems in 14-MeV neutron activation analysis for trace oxygen, 
Anal. Chem. 41, No. 1, 168-170 (January 1969). 

Nemoto, T., Wait, D. F., Microwave circuit analysis using the equivalent genera- 
tor concept. IEEE Trans. Microwave Theory Tech. MTT-16, No. 10, 866-873 
(October 1968). 

Newman, M., A bound for the number of conjugacy classes in a group, J. London 
Math. Soc. 43, 108-110 (1968). 

Newman, M., A diophantine equation, J. London Math. Soc. 43, 105-107 (1968). 

228 



Newman, M., Maximal normal subgroups of the modular group. Proc. Am.. Math. 

Soc. 19, No. 5, 1138-1144 (October 1968). 
Newman, M., Some results on roots of unity, with an application to a diophantine 

problem, Aequat. Math. 2, No. 2/3, 163-166 (Nov. 28, 1967). 
Newton, C. J., Ruff, A. W., Jr., X-ray studies of plastically deformed silver al- 
loys — effects due to oxygen, hydrogen, and tin solutes, Ad van. X-Ray Anal. 12, 

316-328 (1969). 
Nimeroff, I., A survey of papers on degree of metamerism, Color Eng. 6, No. 6, 

44-46 (November-December 1968). 
Nimeroff, I., Schleter, J. C, Professor Harry J. Keegan : colorimetrist's spectro- 

photometrist, J. Appl. Opt. 8, No. 4, 757-761 (April 1969). 
Norton, R. B., Aeronomy, Encyclopedia of Atmospheric Sciences and Astrogeology, 

R. W. Fairbridge, Ed., pp. 3-7 (Reinhold Publ. Co., New York, N.Y., 1967). 
O'Connell, J., An isospin sum rule for photonuclear reactions, Phys. Rev. Letters 

22, No. 24, 1314-1316 (June 16, 1969). 
Odabasi, H., Spectrum of doubly ionized lanthanum (La III), J. Opt. Soc. Am. 

57, 1459-1463 (1967). 
Okabe, H., Photodissociation of HNs in the vacuum-ultraviolet production and 

reactivity of electronically excited NH, J. Chem. Phys. 49, No. 6, 2726-2733 
(Sept. 15, 1968). 
Olver, F. W. J., An extension of Miller's algorithm, Aplikace Mat. 13, 174-176 

(1968). 
Olver, F. W. J., Error bounds for the Laplace approximation for definite integrals, 

J. Approxi. Theory 1, 293-313 (1968). 
Omar, A., Peterson, R. L., On the validity of the Boltzmann relaxation equation, 

Physica 39, No. 1, 156-160 (July 1, 1968) . 
O'Reilly, D. E., Tsang, T., On the order-disorder transition in ferroelectric 

ammonium sulfate, J. Chem. Phys. Letter to Editor 50, No. 5, 2274-2275 

(Mar. 1, 1969). 
Otto, E. M., Rates of dissociation of Ag 2 2 , J. Electrochem. Soc. 115, No. 9, 878- 

881 (September 1968). 
Paabo, M., Bates, R. G., Standards for a practical scale of pD in heavy water, 

Anal. Chem. 41, No. 2, 283-285 (February 1969). 
Pechukas, P., Generalized Langevin equation of Mori and Kubo, Phys. Rev. 164, 

No. 1, 164-175 (Dec. 5, 1967). 
Pecker, J-C, Thomas, R. M., Saturation in Fraunhofer lines, Observatory Letter 

88, No. 964, 115-117 (June 1968). 
Peiser, H. S., The relative magnitude of jump rates for point-defect paths between 

equivalent sites around a trap, J. Korean Phys. Soc. 1, No. 1, 5-8 (March 1968). 
Peiser, H. S., Wachtman, J. B., Jr., Jump rates for point defects in special posi- 
tions held by a trapping centre of cubic symmetry, Chapter 12 in Physics of 

the Solid State, S. Balakrishna, M. Krishnamurty and Rao B. Ramachandra, 

Eds., pp. 207-222 (Academic Press Inc., New York, N.Y., 1969). 
Pella, P. A., DeVoe, J. R., Snediker, D. K., Problems in using Mossbauer spec- 
trometry for quantitative analysis: application to tin, Anal. Chem. 41, No. 1, 

46-50 (January 1969). 
Penner, S., Handling high-energy high-power electron beams, Record IEEE 9th 

Annual Symp. Electron, Ion and Laser Beam Technology, Berkeley, Calif., 

May 9-11, 1967, No. F-79, pp. 50-61 (1967) . 
Peterson, R. L., Short-range magnetic order in a modified Weiss molecular-field 

theory, Phys. Rev. 171, No. 2, 586-590 (July 10, 1968). 
Plummer, E. W., Gadzuk, J. W., Young, R. D., Resonance tunneling of field 

emitted electrons through adsorbates on metal surfaces, Solid State Oommun. 

7, 487-491 (1969). 
Pong, W., Photoemission from Al-AbOa films in the vacuum ultraviolet region, 

J. Appl. Phys. 40, 1733-1739 (1969). 
Pool, K. H., Bates, R. G., Thermodynamics of hydrochloric acid in 95 volume 

percent (92.41 mass percent) ethanol from e.m.f. measurements at 5 to 50° C, 

J. Chem. Thermodynamics 1, 21-29 (1969). 
Potzick, J., Ac-dc regulator-modulator, Rev. Sci. Instr. 39, No. 8, 1219-1220 

(August 1968). 
Powell, C. J., Characteristic energy losses of 8-keV electrons in liquid Al, Bi, In, 

Ga Hg, and Au, Phys, Rev. 175, No. 3, 972-982 (Nov. 15, 1968). 
Powell, C. J., Interaction of electrons with solids, Chapter 9.2 in Atomic and 

Electron Physics, Atomic Interactions, Vol. 7, Methods of Experimental 

Physics, B. Bederson, Ed., Part B, pp. 275-305 (Academic Press Inc., New 

York, N.Y., 1968). 

229 



Powell, C. J., Analysis of optican- and inelastic-electron-scattering data. Para- 
metric calculations, J. Opt. Soc. Am. 59, No. 6, 738-743 (June 1969). 

Powell, P. L., Clark, A. F., Fickett, F. P., Longitudinal magneto resistance of pure 
copper ( Proc. Conf. Electron Mean Free Paths in Metals, Zurich, Switzerland, 
Sept. 3-5, 1968), Phys. Kondeng. Materie 9, 104-112 (Lange and Springer, 
Berlin, West Germany, 1969). 

Przybylowicz, E. P., Smith, G. W., Suddueth, J. E., Nargolwalla, S. S., Activation 
analysis of halogens in photographic emulsions using a neutron generator, 
Anal. Chem. 41, No. 6, 819-823 (May 1969). 

Quindry, T. L., Transmissibility measurements for the determination of struc- 
tural damping. (Proc. Vibrations Conf., Philadelphia, P'a., Mar. 30- Apr. 2, 
1969), Preprint No. 69-VIBR-36, 7 pages (American Society of Mechanical 
Engineers, New York, N.Y. 1969). 

Radford, H. E., Scanning microwave echo box spectrometer, Rev. Sci. Instr. 39, 
No. 11, 1687-1691 (November 1968). 

Radziemski, L. J., Jr., Kaufman, V., Wavelengths, energy levels, and analysis of 
neutral atomic chlorine (01 I), J. Opt. Soc. Am. 59, No. 4, 424-443 (Apr. 1969). 

Rains, T. O, Chemical aspects of atomic absorption, Am. Soc. Testing Mater. 
Spec. Tech. Publ. 443, 19-36 (1969). 

Rains, T. O, Chemical interferences in condensed phase, Chapter 12 in Flame 
Emission and Atomic Absorption Spectrometry, J. A. Dean and T. C. Rains, 
Eds., 1, 349-379 (Marcel Dekker Inc., New York, N.Y., June 1969). 

Rains, T. O, Menis, O., High-precision flame emission spectrometry, Spectrometry 
Letters 2, No. 1, 1-7 (1969). 

Raveche, H. J., Green, M. S., On the consistency of the Yvon-Born-Green 
hierarchy and its truncations, J. Chem. Phys. 50, No. 12, 5334-5336 (June 15, 
1969). 

Ray, O. D., Tsukishima, T., Hyland, R. N., McLane, C. K., Carpenter, R. J., 
Analysis of a frequency-swept one-bit digital correlator, J. Appl. Phys. 39, 
No. 8, 3534-3542 (July 1968). 

Rebbert, R. E., Ausloos, P., The photolysis of methane at 584 A, J. Am. Chem. 
Soc. 90, 7370-7371 (1968). 

Reed, R. P., Low temperature mechanical properties of welded and brased copper 
(Proc. 1968 Cryogenic Engineering Conf., Cleveland, Ohio, Aug. 19-21, 1968), 
Chapter in Advances in Cryogenic Engineering 14, 83-87 (Plenum Press, Inc., 
New York, N.Y., 1969). 

Reeve, G. R., A heterodyne near-zone field-strength meter, IEEE Trans. Instr. 
Meas. IM-18, No. 1, 32-37 (March 1969). 

Rhodes, I., The importance of the glossary storage in machine translation, 
Chapter in Machine Translation, A. D. Booth, Ed., pp. 431-449 (North-Holland 
Publ. Co., Amsterdam, the Netherlands, 1967). 

Rhodes, I., The mighty man-computer team, Blanch Anniversary Volume, pp. 
277-284 (Aerospace Research Laboratories, Office of Aerospace Research, 
U.S. Air Force, Arlington, Va., February 1967). 

Risley, E. W., Discontinuity capacitance of a coaxial line terminated in a cir- 
cular waveguide, IEEE Trans. Microwave Theory Tech. MTT-17, No. 2, 86-92 
(February 1969). 

Roach, F. E., Diffuse galactic light, Chapter in Modern Astrophysics : A 
Memorial to Otto Struve, M. Hack, Ed., pp. 49-66 (Gordon and Breach, New 
York, N.Y., 1967). 

Roach, F. E., The brightness of the zodiacal light at the ecliptic pole (Proc. 
Symp. Meteor Orbits and Dust, Cambridge, Mass., Aug. 9-19, 1965), Smith- 
sonian Contributions to Astrophysics, F. L. Whipple, Ed., II, 225-226 (Smith- 
sonian Institution Astrophysics Observatory, Cambridge, Mass., 1967). 

Robbins, C. R., Growth of strontium titanate from a silica flux, J. Crystal Growth 
2,402-404 (1968). 

Robbins, C. R., Synthetic CaTiSiOs and its germanium analogue (CaTiGe0 5 ), 
Mater. Res. Bull. 3, 693-698 (1968). 

Robbins, R. F., Reed, R. P., Tensile properties of neoprene below the glass transi- 
tion temperature (Proc. 1967 Cryogenic Engineering Conf., Stanford University, 
Stanford, Calif., Aug. 21-23, 1967), Chapter in Advances in Cryogenic Engi- 
neering 13, 252-258 (Plenum Press Inc., New York, N.Y., 1968). 

Romanoff, M., Performance of ductile-iron pipe in soils, J. Am. Water Works 
Assoc. 60, No. 6, 645-655 (June 1968) . 

Rossmassler, S. A., Modification of dissemination channels for scientific infor- 
mation, J. Chem. Doc. 9, No. 1, 17-19 (February 1969). 

Rothwell, G. J., The performance concept: A basis for standards development, 
ASTME Vectors 1969/2, 23-25 (March-April 1969). 

230 



Rubin, R. J., Momentum autocorrelation function of a heavy particle in a 
finite crystal, J. Am. Chem. Soc. 90, 3061-3063 (1968) . 

Rubin, R. J., Transmission properties of an isotopically disordered one-dimen- 
sional harmonic crystal, J. Math. Phys. 9, No. 12, 2252-2266 (December 1968). 

Ruch, R. R., DeVoe, J. R., Radiochemical separation of copper by amalgam 
exchange, Anal. Chem. 39, No. 11, 1333-1335 (September 1967). 

Rush, J. J., Melveger, A. J., Farrar, T. C, Tsang, T., Laser-Raman spectra and 
hindered rotation in the phosphonium halides, Chem. Phys. Letters 2, No. 8, 
621-624 (1968). 

Ruthberg, S., Calibration to high precision in the medium vacuum range with 
stable environments and micromanometer, J. Vacuum Sci. Technol. 6, No. 3, 
401-412 (May- June 1969). 

Ryan, J. V., Federal Government's role and activities in consumer safety. The 
role of the Fabric Flammability Section, Proc, Spring Workship, Home Conf., 
5 pages, National Safety Council, General Session, Washington, D.C., May 26, 
1969. 

Ryan, J. V., Flammable fabrics act and its implementation, Mod. Textiles Mag. 
L, No. 3, 67-70 (March 1969) . 

Ryan, J. V., The flammable fabrics act and its implementation, Proc. Second 
Annual Meeting Information Council on Fabric Flammability, New York, N.Y., 
Dec. 3, 1968, pp. 231-237 (Information Council on Fabric Flammability, New 
York, N.Y., 1968). 

Sadowski, W. L., On some aspects of the eigenf unction expansion of the solution 
of the nonlinear Vlasov equation (Proc. Computer Simulation of Plasma and 
Many-Body Problems, Williamsburg, Va., Apr. 19-21, 1967), Natl. Aeronaut. 
Space Agency Spec. Publ. 153, 433-440 (.1967). 

Sanderson, B. T., Romanoff, M., Performance of commercially pure titanium in 
corrosive soils, Mater. Production 8, No. 4, 29-32 (April 1969). 

Santone, L. C, Application of systems analysis to urban problems, International 
City Manager's Association Municipal Yearbook, pp. 225-232 (1969). 

Santoro, A., Mighell, A. D., Zocchi, M., Reimann, C. W., The crystal and molecu- 
lar structure of hexakis ( imidazole )Ni( II) nitrate, Acta. Cryst. B25, No. 3, 
842-847 (April 1969). 

Santoro, A., Weir, C. E., Block, S., Piermarini, G. J., Absorption corrections in 
complex cases. Application to single crystal diffraction studies at high pressure, 
J. Appl. Cryst. 1, Part 2, 101-107 (June 1968). 

Sarachman, T. N., Microwave spectrum of cis-2-butene, J. Chem. Phys. 49, No. 
7, 3146-3149 (Oct. 1, 1968). 

Saunders, J. B., Bruening, R. J., A new interferometric test and its application 
to the 84-in. reflecting telescope at Kitt Peak National Observatorv, Astron. 
J. 73, No. 6, 415-531 (August 1968) . 

Saylor, C. P., The freezing staircase method, Chapter 11 in Purification of 
Inorganic and Organic Materials, M. Zief, Ed., pp. 125-138 (Marcel Dekker 
Inc., New York, N.Y., 1969). 

Scala, A. A., Ausloos, P., Gas-phase photolysis and radiolysis of cyclopropane, 
J. Chem. Phys. 49, No. 5, 2282-2290 (Sept. 1, 1968). 

Schafer, G. E., Precision microwave measurements — today and tomorrow, Micro- 
wave J. 12, No. 6, 25-28 (June 1969) . 

Schafft, H. A., Avoiding second breakdown, Proc. XIII Intern. Scientific Con- 
gress on Electronics, Rome, Italy, June 1966, pp. 119-130 (Rassegna Interna- 
zionale Elettronica Nucleare Teleradiocinematografica. Rome, Italy, 1966). 

Scharf, K., Steady-state response of silicon radiation detectors to X and gamma 
rays, Proc. Symp. Physics and Nondestructive Testing, ITT Research Institute, 
Chicago, 111., Sept. 27-30, 1966, 1, 235-298 (Air Force Materials Laboratory, 
Wright-Patterson Air Force Base, Ohio, 1968). 

Scheer, M. D., Fine, J., The desorption kinetics of CI- and I~ on Mo and Ta as 
determined by the pulsed-beam method (Proc. Sixth Intern. Symp. Rarefied 
Gas Dynamics, Cambridge, Mass., July 22-26, 1968), Chapter in The Measure- 
ment of Sticking Coefficients at High Temperatures Using the Isotopic Mixing 
Method II, 1469-1477 (Academic Press, Inc., New York, N.Y., 1969). 

Scheer, M. D., Fine, J., The electron affinity of lithium, J. Chem. Phys. 50, No. 
10, 4343-4347 ( May 15, 1969 ) . 

Scheer, M. D., Fine, J., The reaction of carbon monoxide with a tantalum sur- 
face heated above 2000° K, Surface Sci. 12, No. 2, 102-107 (September 1968). 

Scheer, M. D., Klein, R., Low-temperature oxygen atom addition to olefins. III. 
Transition state and the reaction with cis- and trans -2-butenes, J. Phys. Chem. 
73, No. 3, 597-601 (March 1969). 

231 



Schindler, P. W., Heterogeneous equilibria involving oxides, hydroxides, car- 
bonates and hydroxide carbonates (Proc. Symp. Division of Water, Air, and 
Waste Chemistry, 151st Meeting of the American Chemical Society, Pittsburgh, 
Pa., March 1966), Chapter in Equilibrium Concepts in Natural Water Systems, 
Advances in Chemistry Series 67, 196-221 (American Chemical Society, New 
York N.Y., 1967). 

Schmidt, L. B., Case, W. E., Harrington, R. D., Surface dependence of ferrimag- 
netic resonance fields in polycrystalline NiAl ferrite, Proc. IEEE 56, No. 7, 
1236-1237 (July 1968). 

Schwedtfeger, W. J., Discussion of the paper "Method of estimating corrosion of 
highway culverts by means of polarization curves", by R. I. Lindberg, Highway 
Research Record No. 204, Metal Corrosion, Publ. 1535, p. 8 (Natl. Acad. Sci.- 
Natl. Res. Council, Washington, D.C., 1967 ) . 

Schweitzer, W. G., Jr., Saturated absorption by neon inside a 6328 A laser with 
a mixture of neon isotopes in its gain tube, Appl. Phys. Letters 13, No. 11, 
367-368 (Dec. 1, 1968). 

Seidel, G. P., Neutron radiation hardening of polycrystalline iron, Radiation 
Effects 1, 177-190 (1969). 

Sengers, J. V., Transport properties of compressed gases, Chapter in Recent Ad- 
vances in Engineering Science, A. C. Eringen, Ed., Ill, 153-196 (Gordon and 
Breach Science Publ. Inc., New York, N.Y., 1968) . 

Shah, J. A., Huber, M. G., Danos, M., Separability of the nuclear residual two- 
body interaction, Physics Letters 28B, No. 6, 381-383 (Jan. 6, 1969). 

Shapiro, J. T., Madden, R. P., On the optical constants of polystyrene in the 
vacuum ultraviolet, J. Opt. Soc. Am. 58, No. 6, 771-775 (June 1968). 

Sher, A. H., Lithium-ion drift mobility in germanium, J. Appl. Phys. 40, No. 6, 
2600-2607 (May 1969). 

Shideler, R. W., Interfacing a teletypewriter to nuclear instruments used for 
computer-coupled activation analysis, Proc. 1965 Intern. Conf. Modern Trends 
in Activation Analysis, College Station, Texas, Apr. 1965, pp. 236-242 (1965). 

Shimizu, A., Calculations of the penetration of gamma rays through slabs by the 
method of invariant imbedding, Nucl. Sci. Eng. 32, 184-194 (May 1968). 

Shimizu, A., Calculation of the penetration of gamma rays through two-layer 
slabs, Nucl. Sci. Eng. 32, 385-391 (June 1968). 

Shirk, J. S., Bass, A. M, Matrix-isolation spectra of discharge "sputtered" 
metals, J. Chem. Phys. 49, No. 11, 5156-5160 (Dec. 1, 196S). 

Shirley, J. H., Dynamics of a simple maser model, Am. J. Phys. 36, Part 1, No. 
11, 949-963 (November 1968). 

Shirley, J. H., Validity of the semiclassical approximation in maser theory, 
Phys. Rev. 181, No. 2, 600-609 (May 10, 1969). 

Shives, T. R., Bennett, J. A., The effect of environment on the fatigue properties 
of selected engineering alloys, J. Mater. 3, No. 3, 695-715 (1968). 

Shuler, K. E., Reaction cross sections, rate coefficients and nonequilibrium 
kinetics (Lecture, NATO Summer School on Theoretical Chemistry, Constance, 
Germany, Summer 1965), Chapter in Chemische Elementarprozesse, H. Hart- 
mann, Ed., pp. 1-22 ( Springer- Verlag, Berlin, Germany, 1968). 

Shumaker, J. B., Jr., Franck-Condon factors for high rotational levels of nitrogen, 
J. Quant. Spectry. Radiative Transfer 9, 153-156 (1969). 

Shumaker, J. B., Jr., Popenoe, C. H, Experimental test of H 3 Stark-broadening 
theory at high electron densities, Phys. Rev. Letters 21, No. 15, 1046-1048 
(Oct. 7, 1968). 

Sieck, L. W., Continuum emission from Xenon in the vapor phase induced by 
absorption of 1470^1 radiation, J. Phys. Chem. 72, No. 9, 3129-3133 ( Septem- 
ber 1968). 

Sieck, L. W., Xenon-photosensitized decomposition of methane at 1470 A, J. Chem. 
Phys. 50, No. 4, 1748-1753 (Feb. 15, 1969). 

Silverman, S., Reflections on bioengineering (Proc. Symp. Engineering Sig- 
nificance of the Biological Sciences, Pittsburgh, Pa., Jan. 25-27, 1967), Chapter 
in Bioengineering — An Engineering View, pp. 103-106 (San Francisco Press 
Inc., San Francisco, Calif., June 1968). 

Simmons, J. A., Coriell, S. R., Solution of the Stefan problem for whisker evap- 
oration, J. Appl. Phys. 39, No. 7, 3459-3463 (June 1968). 

Simmons, J. D., Bass, A. M., Tilford, S. G., The fourth positive system of carbon 
monoxide observed in absorption at high resolution in the vacuum ultraviolet 
region, Astrophys. J. 155, 345-358 (January 1969). 

Sitterlv, O. M., Forbidden transitions in atoms : catalogs and identifications, Mem. 
Soc. Roy. Sci. Leige V, No. 16. 17-29 (1969). 

232 



Smith, E. W., Hooper, C. F., Jr., Comments on "Ion microfield distributions as 
used in plasma line broadening theories", J. Quant. Spectry. Radiative Transfer 
8, No. 9, 1617-1619 (September 1968). 

Smith, G. W., Becker, D. A., Preparation of an NBS biological standard reference 
material for trace elemental analysis, Proc. Nuclear Activation Techniques in 
the Life Sciences, Amsterdam, the Netherlands, May 8-12, 1967, pp. 197-207 
(International Atomic Energy Agency, Vienna, Austria, 1967) 

Smith, R. V., Current developments in cryomedicine, Cryogenics 9, No. 2, 84-89 
(April 1969). 

Smith, R. V., Review of heat transfer to helium I, Cryogenics 9, No. 1, 11-19 
(February 1969). 

Smith, R. V., Review of heat transfer to helium I, Proc. 1968 Summer Study on 
Superconducting Devices and Accelerators, Brookhaven National Laboratory, 
Upton, N.Y., June 10-July 19, 1968, Part I, BNL 50155 (C-55), pp. 249-292 
(Clearinghouse for Federal Scientific and Technical Information, Springfield, 
Va., April 1969, $3.00). 

Smith, S. J., Photodetachment, Chapter in Methods in Experimental Physics, 
Vol. 7, Atomic and Electron Physics, B. Bederson and W. L. Fite, Eds., pp. 
179-208 (Academic Press Inc., New York, N.Y., 1968) . 

Sparks, L. L., Powell, R. L., Progress on cryogenic thermocouples (Proc. 1968 
Cryogenic Engineering Conf., Cleveland, Ohio, Aug. 19-21, 1968), Chapter in 
Advances in Cryogenic Engineering 14, 316-321 (Plenum Press, Inc., New York, 
N.Y., 1969). 

Spijkerman, J. J., Ruegg, F. C, May, L., The use of Mossbauer spectroscopy in 
iron coordination chemistry, Chapter in Mossbauer Effect Methodology, 2, 
85-93 (Plenum Press Inc., New York, N.Y., 1966). 

Steel, N. M., Production of synthetic food materials: A statistical survey, Proc. 
Second Intern. Conf. Women Engineers and Scientists, 30 pages (Women's 
Engr. Society, London, England, 1968). 

Steiner, B., The cross section for the photodetachment of electrons from I - , Phys. 
Rev. 173, No. 1, 136-142 (Sept. 5, 1968). 

Steiner, B., Photodetachment of electrons from SH~, J. Cheni. Phys. 49, No. 11, 
5097-5104 (Dec. 1, 1968). 

Stephens, R. E., Sutton, L. E., Diffraction image of a point in the focal plane 
and several out-of -focus planes, J. Opt. Soc. Am. 58, No. 7, 1001-1002 (July 
1968). 

Stevens, M. E., Automatic analysis, Encyclopedia of Library and Information 
Science, A. Kent and H. Lancour, Eds., 2, 144-184 (Marcel Dekker Inc., New 
York, N.Y., 1969). 

Stevens, M. E., Progress and prospects in mechanized indexing (Proc. Symp. on 
Mechanized Abstracting and Indexing, Moscow, U.S.S.R., Sept. 28-Oct. 1, 
1966), UNESCO/NS/209, 51 pages (United Nations Educational Scientific and 
Cultural Organization, Paris, France, April 1967). 

Stevens, M. E., Selected pattern recognition projects in Europe, Pattern Recog- 
nition 1, No. 2, 103-118 (November 1968). 

Stevens, M. E., Luhn, H. P., Information scientist, Chapter in H. P. Luhn : Pioneer 
of Information Science — Selected Works, C. K. Schultz, Ed., pp. 24-30 (Spartan 
Books, New York, N.Y., 1968) . 

Steward, W. G., Smith, R. V., Brennan, J. A., Cooldown time for simple cryogenic 
pipelines (Proc. Tenth Midwestern Mechanics Conf., Colorado State Uni- 
versity, Fort Collins, Colo., Aug. 21-23, 1967), Chapter in Developments in 
Mechanics 4, 1513-1525 (Johnson Publ. Co., Boulder, Colo., 1968). 

Stiehler, R. D., History of measurement and the SI units, Mater. Res. Std. 9, 
No. 6, 14-18 (June 1969). 

Stiehler, R. D., Parks, E. J., Linnig, F. J., Stiffening of elastomers by organic 
fillers, Appl. Poly. Symp. No. 7, 143-153 (1968). 

Straty, G. C, Bellows-sealed valve for reactive gases at moderately high pres- 
sures, Rev. Sci. Instr. 40, No. 2, 378-379 (February 1969) . 

Strobridge, T. R., Refrigeration at 4° K, Proc. 1968 Summer Study on Super- 
conducting Devices and Accelerators, Brookhaven National Laboratory, Upton, 
N.Y., June 10-July 19, 1968, Part I, BNL 50155 (C-55), pp. 193-204 (Clearing- 
house for Federal Scientific and Technical Information, Springfield, Va., April 
1969, $3.00). 

Strobridge, T. R., Refrigeration for superconducting and cryogenic systems. 
(Proc. 1969 Particle Accelerator Conf., Washington, D.C., Mar. 5-7, 1969), 
IEEE Trans. Nucl. Sci. NS-16, Part I, No. 3, 1104-1108 (June 1969) . 

233 



Strobridge, T. R., Review of the cryogenics session second week of the Brook- 
haven summer study on superconducting devices and accelerators, Proc. 1968 
Summer Study on Superconducting Devices and Accelerators, Brookhaven 
National Laboratory, Upton, N.Y., June 10-July 19, 1968, Part I, BNL 50155 
(C-55), pp. 368-375 (Clearinghouse for Federal Scientific and Technical In- 
formation, Springfield, Va., April 1969, $3.00). 

Stromberg, R. R., Polymer adsorption on substrates (Proc. Symp. Interface 
Conversion Polymer Coatings, General Motors Research Laboratories, Detroit, 
Mich., October 1967), Chapter in Interface Conversion for Polymer Coatings, 
P. Weiss and G. D. Cheever, Eds., pp. 321-337 (American Elsevier Publ. Co., 
Inc., New York, N.Y., 1969) . 

Sugar, J., Nuclear magnetic dipole moment of 163 Ho, J. Opt. Soc. Am. 58, No. 11, 
1519-1523 (November 1968). 

Sukle, D. J., Wells, J. S., Fine structure in EPR of Mn 2+ in zinc sulfate, Phys. 
Rev. 180, No. 2, 445-450 (Apr. 10, 1969). 

Suzuki, G., Quantitative methods for decisionmaking, Chapter in Management: 
Concepts and Practices, F. R. Brown, Ed., Chapt. VIII, pp. 155-193 (Indus- 
trial College of the Armed Forces, Washington, D.C., 1967). 

Swanson, N., Codling, K., Excitation of K-shell electrons in Be by soft x-rays 
and 20-keV electrons, J. Opt. Soc. Am. 58, No. 9, 1192-1194 (September 1968). 

Swartzendruber, L. J., Variable temperature Mossbauer effect spectrometer with 
provision for longitudinal external fields, Nucl. Instr. Methods 69, 101-105 
1969). 

Swartzendruber, L. J., Bennett, L. H., Watson, R. E., Dilute 57 Fe Mossbauer 
studies in Cu-Ni alloys, J. Appl. Phys. 40, No. 3, 1489-1490 (Mar. 1, 1969). 

Swartzendruber, L. J., Ulmer, F. H., Coleman, J. A., Direct reading instrument 
for silicon and germanium four-probe resistivity measurements, Rev. Sci. 
Instr. 39, No. 12, 1858-1863 (December 1968). 

Taggart, H. E., Field strength and RFI standards at the National Bureau of 
Standards, Proc. IEEE Electromagnetic Compatibility Conf., Seattle, Wash- 
ington, July 23-25, 1968, pp. 149-158 (1968). 

Tanttila, W. H., Mahler, R. J., James, L. W., Magnetic parametric nuclear spin 
saturation, Appl. Phys. Letters 13, No. 1, 27-29 (July 1, 1968). 

Tate, E. L., Variations on a theme: Government and library cooperation, D.C. 
Libraries 39, No. 3, 53-55 (1968) . 

Tauber, S. J., Imprecision — problems for information processing, Am. Doc. 19, 
No. 4, 413-414 (October 1968) . 

Taylor, J. K., Modern electrochemistry, Ind. Res. 10, No. 10, 68-74 (October 
1968). 

Thomas, A. M., Monte Carlo study of vacuum vane gauge design criteria, J. 
Vacuum Sci. Technol. 5, No. 6, 187-193 (November-December 1968). 

Thomas, R. N., Symposium on Wolf-Rayet stars : A summary, Astrophysical 
Letters 2, No. 3, 147-148 (Oct. 4, 1968) . 

Thompson, B. A., LaFleur, P. D., Rapid group radiochemical separations for 
activation analysis of steels, Anal. Chem. 41, No. 6, 852-855 (May 1969). 

Tipson, R. S., Cohen, A., Reaction of some sulfonic esters of D-mannitol with 
methoxide ; synthesis of 2,3 :4,5-dianydro-D-iditol, Carbohydrate Res. 7, 232- 
243 (1968). 

Tipson, R. S., West, B. F., Brady, R. F., Acid-catalyzed hydrolysis of isopropy- 
lidene acetals of some 2-pentuloses and 2-hexuloses, Carbohydrate Res. 10, 
181-183 (1969). 

Toots, J. Fowler, H. A., Marton, L., Reflectance and 1/e resonance of beryllium 
in the far ultraviolet, Phys. Rev. 172, No. 3, 670-676 (Aug. 15, 1968). 

Torrance, K. E., Orloff, L., Rockett, J. A., Experiments on natural convection in 
enclosures with localized heating from below, J. Fluid Mech. 36, Part 1, 21-31 
(1969). 

Torrance, K. E., Orloff, L., Rockett, J. A., Numerical study of natural convection 
in an enclosure with localized heating from below — creeping flow to the onset 
of laminar instability, J. Fluid Mech. 36, Part 1, 33-54 (1969). 

Travis, J. C, Spijkerman, J. J., Mossbauer spectroscopy with Ni 61 , Chapter in 
Mossbauer Effect Methodology, 4, 237-259 (Plenum Press Inc., New York, N.Y., 
1968). 

Trembath, C. L., Wait, D. F., Engen, G. F., Foote, W. J., A low-temperature 
microwave noise standard, IEEE Trans. Microwave Theory Tech. MTT-16, 
No. 9, 709-714 ( September 1968) . 

Truesdell, C, The non-linear field theories of mechanics, Encyclopedia of Physics 
III, Part 3, 602 pages ( Springer-Verlag, Berlin, Germany, 1965). 

234 



Tsai, D. H., Beckett, C. W., Shock wave propagation in a two-dimensional crys- 
talline lattice (Proc. Intern. Union of Theoretical and Applied Mechanics: 

Intern. Syrnp. Behavior of Dense Media Under High Dynamic Pressure, Paris, 

France, Sept. 11-15, 1967), Chapter in The Behavior of Dense Media Under 

High Dynamic Pressure, pp. 99-108 (Gordon and Breach Science Publ. Inc., 

New York, N.Y., 1968). 
Tsang, T., Self-consisten correlation function approximation in ising ferromag- 

nets, Physica 42, 1-11 (1969) . 
Tsang, T., Farrar, T. 0., Nuclear magnetic relaxation studies of internal rotations 

and phase transitions in borohydrides of lithium, sodium, and potassium. J. 

Chem. Phys. 50, No. 8, 3498-3502 (Apr. 15, 1969) . 
Tsang, T., Farrar, T. C, Rush, J. J., Proton magnetic resonance and hindered 

rotation in phosphonium halides and ammonium iodide, J. Chem. Phys. 49, 

No. 10, 4403-4406 (November 1968). 
Tsang, W., Thermal decomposition of 3,4-dimethylpentent-l, 2,3,3-trimethylpen- 

tane, 3,3-dimethylpentane, and isobutylbenzene in a single pulse shock tube, 

Intern. J. Chem. Kinetics 1,245-278 (1969). 
Tschuikow-Roux, E., Photolysis of propene at 1470 A, J. Phys. Chem. Note 71, 

2355 (1967). 
Turgel, It. S., A comparator for thermal ac-dc transfer standards, ISA Trans. 6, 

No. 4, 286-292 (1967). 
Ugiansky, G. M., Ellinger, G. A., Corrosion of Monel 400 in high C0 2 well water, 

Corrosion 24, No. 5, 134-136 (May 1968). 
Ugiansky, G. M., Skolnick, L. P., Kruger, J., Stiefel, S. W., Rate-controlling step 

in stress corrosion cracking, Nature 218, No. 5147, 1156-1157 (June 22 ,1968). 
Utech, H. P., Early, J. G., On the presence of thermal convection in the kinetics 

experiments of Rigney and Blakely, Act Met. 15, No. 7, 1238-1239 (1967). 
Utech, H. P., Parker, R. L., Early, J. G., Coriell, S. R., The cam equation for a 

thermal-wave generator, J. Appl. Phys. 38, No. 9, 3799-3800 (August 1967). 
Van Blerkom, D., Hummer, D. G., A non-LTE theory of overlapping lines near 

the series limit, Astrophys. J. 154, No. 2, 741-750 (November 1968). 
Veillon, C, Margoshes, M., An evaluation of the induction-coupled, radio-fre- 
quency plasma torch for atomic emission and atomic absorption spectrometry, 

Spectrochim. Acta. 23B, 503-512 (1968). 
Veillon, C, Margoshes, M., A pneumatic solution nebulization system producing 

dry aerosol for spectroscopy, Spectrochim. Acta. 23B, 553-555 (1968). 
Verdier, P. H., A simulation model for the study of the motion of random-coil 

polymer chains, J. Computational Phys. 4, No. 2, 204-210 (1969). 
Vicentini-Mis;soni, M., Sengers, J. M. H. L., Green, M. S., Therodynamic anomalies 

of C0 2 , Xe, and He 4 in the critical region, Phys. Rev. Letters 22, No. 9, 389-393 

(Mar. 3, 1969). 
Vieth, D. L., Yakowitz, H, Tensile loading device for Kossel microdiffraction 

and metallography, Rev. Sci. Instr. 39, No. 12, 1929-1931 (December 1968). 
Viezbicke, P. P., Interactions between nested receiving rhombic antennas, IEEE 

Trans. Ant. Prop. AP-17, No. 1, 16-23 (January 1969). 
Viezbicke, P. P., Why WWV moved to Colorado, Mark 5, 13, No. 3, 14-16 (June 

1968). 
Waclawski, B. J., Hughey, L, R., Madden, R. P., Effect of oxygen adsorption on 

the photoelectron yield from tungsten in the vacuum untraviolet, Appl. Phys. 

Letters 10, No. 11, 305-307 (June 1968). 
Waddell, W. J., Bates, R. G., Intracellular pH, Physiol. Rev. 49, No. 2, 289-329 

(1969). 
Wagman, D. D., Elements of chemical thermodynamics : introduction to thermal 

methods, Chapter 86 in Treatise on Analytical Chemistry, Part I. Theory and 

Practice, I. M. Kolthoff, P. J. Elving, and E. B. Sandell, Eds., 8, 4909-4936 

( Interscience Publ. Inc., New York, N.Y., 1968) . 
Wahsweiler, H. G., Greiner, W., Danos, M., Continuum nuclear structure of O 16 in 

the Eigenchannel Reaction Theory, Phys. Rev. 170, No. 4, 893-906 (June 20, 

1968). 
Wait, D. F., Thermal noise from a passive linear multiport, IEEE Trans. Micro- 
wave Theory Tech. MTT-16, No. 9, 687-691 (September 1968). 
Wait, D. F., Nemoto, T., Measurement of the noise temperature of a mismatched 

noise source, IEEE Trans. Microwave Theory Tech. MTT-16, No. 9, 670-675 

(September 1968). 
Wang, F. E., De Savage, B. F. Buehler, W. J., The irreversible critical range in 

the TiNi transition, J. Appl. Phys. 39, No. 5, 2166-2175 (April 1968). 
Watson, R. E., Bennett, L. H., Freeman, A. J., Comments on "Origin of solvent 

Knight shifts in alloys", Phys. Rev. 179, 590-592 (Mar. 10, 1969). 

235 



Waterstrat, R. M., Crystal structure transformations in VPt produced by plastic 
deformation at room temperature, Trans. Met. Soc. AIME 245, 1360-1361 ( June 
1969). 

Weir, C. E., Piermarini, G. J., Block, S., Single crystal x-ray diffraction at high 
dentistry, J. Am. Dental Assoc. 78, No. 3, 536-541 (March 1969). 

Waterstrat, R. M., Evaluation of a gallium-palladium-tin alloy for restorative 
forms of C 6 H 6 ,CS2,Br 2 ,OCl4, and KNO, J. Chem. Phys. 50, No. 5, 2089-2093 
(Mar. 1, 1969). 

Weir, C. E., Piermarini, G. J., Block, S., Crystallography of some high-pressure 
pressure, Proc. American Orystallographic Association High Pressure X-ray 
Diffraction Symposium, Seattle, Washington, Mar. 23-29, 1969, 5, 105-111 
(1969). 

Weisman, H. M., Information and the discipline of communication sciences 
(Proc. American Documentation Institute Annual Meeting, New York, N.Y., 
Oct. 22-27, 1967), Chapter in Levels of Interaction Between Man and Informa- 
tion 4, 8-12 (Thompson Book Co., Washington, DC., 1968). 

Weisman, I. D., Bennett, L. H., Quadrupolar echoes in solids, Phys. Rev. 181, 
No. 3, 1341-1350 (May 15, 1969). 

Weisman, I. D., Swartzendruber, L. J., Bennett, L. H., Resonance studies in 
ferromagnetic Fe 2 B and Fe 2 Zr, Phys. Rev. 177, No. 2, 465-471 (Jan. 10, 1969). 

Weiss, A. W., Series perturbations and atomic oscillator strengths : The 2 D series 
of Al i, Phys. Rev. 178, No. 1, 82-89 (Feb. 5, 1969) . 

Weiss, B-Z., Meyerson, M. R., Localized microstructural changes and fatigue 
crack propagation, Trans. Met. Soc. AIME 242, 2515-2518 (1968). 

Weiss, B-Z., Meyerson, M. R., The effect of mean stress of fatigue crack propaga- 
tion in plates under extension and bending, J. Basic Eng. 90, Series D, No. 3, 
414-417 (September 1968). 

Weissberg, A., Data handling systems, Proc. Second Conf. Technical Information 
Center Administration, St. David's, Pa., June 14-17, 1965, TICA 2, A. W. Elias, 
Ed., pp. 75-89 (Spartan Books, Washington, D.C., 1965). 

Weissberg, S. G., Brown, J. E., Osmometry of polymers, Encyclopedia of Polymer 
Science and Technology 9, 659^668 (Interscience Publ. Inc., New York, N.Y., 
1969). 

Weissler, P. G., International standard reference zero for audiometers, J. Acoust. 
Soc. Am. 44, No. 1, 264-275 (July 1968). 

Weitzel, D. H., Sindt, C. F., Daney, D. E., Hydrogen slush density reference sys- 
tem (Proc. 1967 Cryogenic Engineering Conf., Stanford University, Stanford, 
Calif., Aug. 21-23, 1967), Chapter in Advances in Cryogenic Engineering 13, 
523-533 (Plenum Press, Inc., New York, N.Y., 1968) . 

West, E. D., Churney, K. L., A two-body model for the calorimeters with constant- 
temperature environment, J. Appl. Phys. 39, No. 9, 4206-4215 (August 1968). 

West, E. D., Westrum, E. F., Jr., Adiabatic calorimetry from 300 to 800 K, Chapter 
9 in Experimental Thermodynamics, Vol. I, Calorimetry of non-reacting Sys- 
tems, J. P. McCullough and D. W. Scott, Eds., pp. 333-367 (Butterworth and 
Co., London, England, 1968). 

Westrum, E. F., Jr., Furukawa, G. T., McCullough, J. P., Adiabatic low-tempera- 
ture calorimetry, Chapter 5 in Experimental Thermodynamics, Vol. I, Calorim- 
etry of Nonreacting Systems, J. P. McCullough and D. W. Scott, Eds., pp. 
133-214 (Butterworth and Co., London, England, 1968). 

Wexler, A., Calibration of humidity ^measuring instruments at the National 
Bureau of Standards, ISA Trans. 7, No. 4, 356-362 (1968). 

White, H. S., Jr., Data management and standardization, Mod. Data 2, No. 5, 
52-56 (May 1969). 

Wiederhorn, S. M., Fracture surface energy of glass, J. Am. Ceramic Soc. 52, 
No. 2,99-105 (1969). 

Wiederhorn, S. M., Moisture assisted crack growth in ceramics, Intern. J. Frac- 
ture Mech. 4, No. 2, 171-177 (June 1968) . 

Wiese, W. L., Dependence of atomic /-values on nuclear charge (Proc. Conf. 
Beam-Foil Spectroscopy, University of Arizona, Tucson, Ariz., Nov. 20-22, 
1967), Chapter in Beam Foil Spectroscopy, II, 386-406 (Gordon and Breach 
Science Publ. Inc., New York, N.Y., 1968). 

Wiese, W. L., Systematic trends of atomic oscillator strengths in isoelectronic 
sequences, Appl. Opt. 7, No. 12, 2361-2366 (December 1968). 

Wiese, W. L., Weiss, A. W., Regularities in atomic oscillator strengths, Phys. 
Rev. 175, No. 1, 50-65 (Nov. 5, 1968) . 

Wilcox, R. M., Bounds for the isothermal, adiabatic, and isolated static suscep- 
tibility tensors, Phys. Rev. 174, No. 2, 624-629 (Oct. 10, 1968). 

236 









Wildhack, W. A., Improving measurement accuracy for high systems reliability, 
Electronics 41, No. 5, 280 (Mar. 4, 1968) . 

Wildhack W. A., Mason, H. L., Powers, R. S., Jr., Accuracy charts for RF meas- 
urements, Proc. IEEE 55, No. 6, 1056-1063 (June 1967) . 

Williams, E. S., A voltage converter for a new era, Meas. Data 2, No. 6, 75-79 
(November-December 1968) . 

Wims, A. M., Mclntyre, D., Hynne, F., Coexistence curve for 3-methylpentane- 
nitroethane near the critical point, J. Chem. Phys. 50, No. 2, 616-620 (Jan. 15, 
1969). 

Winogradoff, N. N., Kessler, H. K., Compensation and band tailing effects in 
high power room temperature GaAs lasers, Solid State Commun. 5, 155-158 
(1967). 

Wolcott, N. M., Falge, R. L., Jr., Ferromagnetism of CrBeis, Phys. Rev. 171, 
No. 2, 591-595 (July 10, 1968) . 

Wolcott, N. M., Falge, R. L., Bennett, L. H., Magnetic behavior of intermetallic 
compounds of beryllium, J. Appl. Phys. 40, No. 3, 1377-1378 (Mar. 1, 1969). 

Wolcott, N. M., Falge, R. L., Jr., Bennett, L. H., NMR studies in paramagnetic 
and ferromagnetic CrBei 2 , Phys. Rev. Letters 21, No. S, 546-549 (Aug. 19, 1968) . 

Wolfe, W. C, Field study of floor coverings, Flooring 74, No. 11, 52-58 (Novem- 
ber 1968). 

Wolfgang, R., Zare, R. N., Branscomb, L. M., Chemical accelerators, Science 
162, No. 3855, 818-822 (Nov. 15, 1968) . 

Woo, S. B., Branscomb, L. M., Beaty, E. C, Sunlight photodetachment rate of 
ground state 2 ~, J. Geophys. Res. Space Physics 74, No. 11, 2933-2940 (June 1, 
1969). 

Yakowitz, H., Heinrich, K. F. J., Inclusion identification by means of electron 
probe microanalysis, Metallography 1, No. 1, 55-78 (September 1968). 

Yakowitz, H., Michaelis, R. E., Vieth, D. L., Homogeneity characterization on 
NBS spectrometric standards, IV : Preparation and microprobe characteriza- 
tion of W-20% Mo alloy fabricated by powder metallurgical methods (Proc. 
17th Annual Conf., Applications of X-ray Analysis, Estes Park, Colo., Aug. 
21-23, 1968), Chapter in Advances in X-ray Analysis, C. S. Barett, G. R. 
Mallett, and J. B. Newkirk, Eds., 12, 418-438 (Plenum Press Inc., New York, 
N.Y.,1969). 

Yakowitz, H., Vieth, D. L., Heinrich, F. J., Michaelis, R. E., Homogeneity charac- 
terization of NBS spectrometric standards. II : Cartridge brass and low-alloy 
steel ( Proc. 14th Annual Conf. Applications of X-ray Analysis, University of 
Denver, Denver Research Inst., Denver Colo., Aug. 25-27, 1965), Chapter in 
Advances in X-ray Analysis, G. R. Mallett, M. Fay, and W. M. Mueller, Eds., 
9, 289-303 (Plenum Press Inc., New York, N.Y., 1966) . 

Yates, J. T., Jr., Madey, T. E., Electron impact study of the — N 2 state chemi- 
sorbed on tungsten (Proc. Fourth International Materials Symp., Berkeley, 
California, June 1968), Chapter in The Structure and Chemistry of Solid 
Surfaces, Gabor A. Somorjai, Ed., pp. 59-1, 59-27 (John Wiley & Sons, Inc., 
New York, N.Y.,1969). 

Yee, K. W., Deslattes, R. D., Transistorized current stabilizer for X-ray tubes 
with directly heated cathodes, Rev. Sci. Instr. 38, No. 5, 637-638 (May 1967). 

Yolken, H. T., Kruger, J., Thermal regeneration of oxide covered iron [100] and 
[110] surfaces, J. Electrochem. Soc. 114, No. 8, 796-799 (August 1967). 

Yolken, H. T., Kruger, J., Calvert, J. P., Hydrogen in passive films on Fe, Cor- 
rosion Sci. 8, 103-108 (1968). 

Yonemura, G. T., Kasuya, M., Color discrimination under reduced angular sub- 
tense and luminance, J. Opt. Soc. Am. 59, No. 2, 131-135 (February 1969). 

Young, D. S., Mears, T. W., Measurement and standard reference materials in 
clinical chemistry, Clin. Chem. 14, No. 10, 929-943 (October 1968). 

Young, K. F., Forman, R. A., Use of polystyrene beads for manufacture of low 
loss coaxial lines for low temperature research, Rev. Sci. Instr. 39, No. 12, 
1964-1965 (December 1968) . 

Young, R. D., Kuyatt, C. E., Resolution determination in field emission energy 
analyzers, Rev. Sci. Instr. 39, No. 10, 1477-1480 (October 1968). 

Younglove, B. A., Polarizability, dielectric constant, pressure, and density of 
solid parahydrogen on the melting line, J. Chem. Phys. 48, No. 9, 4181-^186 
(May 1,1968). 

Zalubas, R., Present state of analysis of the first spectrum of thorium (Thi), 
J. Opt. Soc. Am. 58, No. 9, 1195-1199 (September 1968). 

Zwanzig, R., Lauritzen, J. I., Jr., Exact calculation of the partition function for 
a model of two-dimensional polymer crystallization by Chain folding, J. Chem. 
Phys. 48, No. 8, 3351-3360 (Apr. 15, 1968). 

237 



PATENTS 

The following U.S. Patents have been granted to NBS inventors and assigned 
to the United States of America, as represented by the Secretary of the Depart- 
ment noted in parentheses: 

Ruehrwein, Robert A., and Hashman, Joseph S., No. 3,378,351, April 16, 1968. 
Complex Compounds of Molecular Oxygen (Army). 

Wall, Leo A., and Antonucci, Joseph M., No. 3,394,190, July 23, 1968. Synthesis 
of Perfluoroparacresol, Polyoxyperfluorobenzylene and Related Monomers and 
Polymers (Navy). 

Henig, Seymour, and Palasky, Ervin C, No. 3,397,392, August 13, 1968. Informa- 
tion Storage and Category Selector (Commerce). 

Thompson, Moody C, Jr., and Vetter, Maurice J., No. 3,400,330, September 3, 
1968. Refractometer That Measures the Difference in Refractive Indices of a 
Gas at Two Frequencies (Commerce). 

Carlson, John G., No. 3,410,100, November 12, 1968. High Vacuum Baffle Using 
Cooled Chevron-Shaped Members (Commerce). 

Cruz, Jose E., No. 3,417,350, December 17, 1968. Variable Impedance Device with 
Relative Rotation Between Conductors ( Commerce ) . 

Bender, Peter L., and Owens, James C, No. 3,424,431, January 28, 1969. A Dis- 
tance Measuring Instrument Using a Pair of Modulated Light Waves (Com- 
merce). 

Wall, Leo A., and Antonucci, Joseph M., No. 3,429,935, February 25, 1969. High 
Temperature Substitution Reactions of Hexafluorobenzene (Navy). 

Thompson, Moody C, Jr., and Wood, Lockett E., No. 3,437,820, April 8, 1969. 
Optical Distance Measuring Equipment Utilizing Two Wavelengths of Light 
in Order to Determine and Compensate for the Density of the Air (Commerce). 

Thompson, Moody C, Jr., and Wood, Lockett E., No. 3,437,821, April 8, 1969. 
Radio — Optical Refractometer for Measuring Integrated Water-Vapor Re- 
f ractivity ( Commerce ) . 



238 

U.S. GOVERNMENT PRINTING OFFICE: 1970 



PENN STATE UNIVERSITY LIBRARIES 



ADoao?nnm 



^ T ° F Co, 




°*GAU Of *